Metformin Wonder Drug

A while back I wrote about why metformin is the number one treatment for Type 2 diabetes. Now new research finds metformin prevents cancer and heart disease and may actually slow aging! Where can I get this stuff?


A study from Scotland found that people on metformin had only roughly half the cancer rate of people with diabetes who weren’t on the drug. This is important, because diabetes is associated with higher risks of liver, pancreas, endometrial, colon and rectum, breast, and bladder cancer.

Nobody could explain how metformin helped, but then Canadian researchers showed that metformin reduces cell mutations and DNA damage. Since mutations and DNA damage promote both cancer and aging, this is striking news. No one thought we could limit mutations before, but perhaps metformin can do it.

A study on mice exposed to cigarette smoke showed that those given metformin had 70% less tumor growth. A small study of humans in Japan showed similar improvements in colorectal cancer outcomes. Metformin is now being studied in clinical trials for breast cancer. The researchers write, “Women with early-stage breast cancer taking metformin for diabetes have higher response rates to [presurgical cancer therapies] than diabetic patients not taking metformin.” They also had better results than people without diabetes.

How Does It Work?
According to Michael Pollak, MD, professor in McGill’s Medicine and Oncology Departments, metformin is a powerful antioxidant. It slows DNA damage by reducing levels of “reactive oxygen species” (ROS). ROS are produced as byproducts when cells burn glucose. Just as oxygen helps fires burn or metals rust, ROS will oxidize (“burn” or “rust”) the nuclei or other parts of cells. ROS are what the antioxidant vitamins are supposed to block. Whether these supplements actually prevent oxidation is unclear.

But metformin apparently does work as an antioxidant. Even better, it mainly acts on cells that are trying to turn cancerous. Gerardo Ferbeyre, MD, PhD, of University of Montreal’s Department of Biochemistry, said, “The drug seems to selectively prevent [ROS] production from … cells with [cancer-causing] mutations.”
Spanish scientists published in the journal Cell Cycle that metformin seems to block cancer in two ways. Like a chemotherapy drug, it blocks certain enzymes cancer cells need to reproduce. But the scientists wrote that metformin’s glucose-lowering and insulin-lowering effects may be more important. Metformin mimics the effect of severely restricting calories. The lowered insulin level enables healthy cells to reproduce better, so they don’t become cancerous.

The American Diabetes Association says that, “Early evidence suggests that metformin is associated with a lower risk of cancer and that [injecting] insulin is associated with an increased cancer risk.” But the effect is not great, so they say “cancer risk should not be a major factor in choosing diabetes therapies for the average patient.” However, if insulin promotes aging and cancer, it seems reasonable to use as little as possible.

As a powerful antioxidant, metformin may actually slow aging. Anti-aging guru Ward Dean, MD, calls metformin “the most effective anti-aging drug there is.” A study of female mice showed those taking metformin lived an average of 37% longer than those without the drug. Although they ate about the same amount of food, the metformin mice weighed less. It has long been known that mice and rats fed very-low-calorie diets live longer. This sounds like metformin is mimicking a low-calorie diet, extending life and preventing cancer while subjects eat normally. Sounds like a good thing.

What is Metformin Anyway?
Metformin is basically a refined herbal medicine derived from a flower called French lilac (Galega officinalis). In Europe, French lilac is also called “Goat’s Rue,” because goats don’t like it — it lowers their blood sugar too much. It has been used as diabetes medicine by healers for centuries.

French diabetologist Jean Sterne was the first to try metformin on humans for the treatment of diabetes. He coined the name “Glucophage” (glucose eater) for the drug and published his results in 1957. It was officially approved for use in Canada in 1972, but not in the US until 1995.

It’s interesting how many of our best medicines are based on natural substances, not developed in any laboratory. Aspirin and penicillin come to mind. Metformin may be in their league for benefiting people.

There are possible harmful effects from metformin. If you are on insulin, you will be in more danger of going low, because metformin turns off the liver’s ability to compensate for low sugars. So it’s probably not for Type 1s. (Editor’s Note: Metformin is currently not approved for use in Type 1 diabetes, but studies are under way to assess its effects on this condition.) It also seems to lower vitamin B12 level, so you might need supplements for that. And it (rarely) causes liver or kidney problems, so you might need to be tested for that occasionally.

If you have Type 2 or 1.5, you might ask your doctor about maxing out on metformin and reducing insulin, or Actos, or other oral drugs. There seem to be many benefits.

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  • jim snell

    Wow! Things are looking up for metformin.

    Excellent comment about metformin. As i use it to shut down dawn effect, I have cgms to catch the situation you mention and any other time spaces when met up to strength in blood.

    Thank you very much for excellent article and detail.

  • JoAnn

    I have always had a strong aversion to manufactured drugs and to injections (the needle aversion thing). I have been pre-diabetic for some time. My starting weight was 238 and I lost 35 pounds over the next 2 years. But I still ended up with full type 2 and have had for 1 1/2 years. I finally got serious about it all when doc says I need to go on insulin. I refuse. I have been extremely focused on my diet for one week. I have dropped AM blood glucose from avg of 225 down to avg of 150. I consume 1500 calories or less per day, eating lots of veggies and proteins. I have been extremely cautious with calculating the carbs, only consuming 100-160 per day. I have been on Metformin since diagmnosed as type 2, 1000mg AM meal and 1000mg PM meal. I have tried other home remedies. I believe in taking cinnamon caplets with each meal and I take a daily B complex with a cardio level multi-vitamin. I have to re-think the metformin. I was hoping to get off it some day, but now it looks like it would be worth continuing long term as I am only 50. I have a very high family history of type 2 on both sides of the family. Gramdma (dad’s side) lived to 93 and was diabetic as most elderly become. She was very careful of her diet and I only hope I can be as regimented for the long term. Mom is 72 and diabetic since 50. She has not managed it at all. She now lives in a nursing home, has a 3/4 foot amputation, Charcot’s feet, severe nueropathy, kidney failure, and so much more. I don’t want that future for myself. Here’s hoping for the best!

  • Patty

    How can you call this a wonder drug when it tears up my stomach. Not everyone can take a drug. there are those of us who have sensitive stomach and have problems with a number of drugs. There is no such things as a miracle drug.

  • JEFF

    I would like to know more about metformin and it’s natural properties. However my MD has prescribed that and I broke out in hives.

  • Martha

    I have type 2 diabetes. I was on glucotrol for years. It was to the point my Dr was considering insulin. Then decided to try Metformin. I have been on it for 6 months and there is a world of difference in my readings. I am so thankful.

  • Carol, AZ

    WOW! Thanks for this article on Metformin. I always carried the desire to limit and finally get off the meds but now I am rethinking that. I lowered my intake from 2000mg to 1500mgs. I do well on the lesser amt but maybe I would do better with the higher limit that was prescribed.

    My AM test usually averages about 120 and I am 77yrs old; haveing been type2 for about 12yrs+. My a/1c is 6.
    I have found that I mostly can eat whatever I want as long as I keep the amts small and I am pretty careful about what I choose to eat.

    Thanks also for this site, I get a lot of good info here.

    Carol, AZ

  • andie

    My mom uses metformin as well as some of her friends and they all have had one unpleasant side effect. All of them have had substantial hair loss! Is this common, has anyone else had this problem?

  • Carol Christiansen

    So perhaps there is a silver lining to having Type 2 for all these years. I’ve always appreciated metformin, but now will see it as a wonder drug.

  • Francie Paper

    Mr. Spero did not mention the current findings that prolonged usage of Metformin causes a Vitamin B12 deficiency — not a good thing. Please comment . . .

  • becky

    Get an endocrinologist for a second opinion. IT couldn’t possibly hurt.

  • Teresa

    I have taken Metformin for approx. three years and while sugars have gone down (a little above normal) the side effects have far outweighed the benefits. I am nauseous about 75% of the time, I often have diarrhea and/or vomiting. There are foods I can no longer look at, let alone eat. When I told my doctor she told me I could take as much Pepto Bismal as I wanted. This hardly seems like a workable solution.

  • Donna

    Delighted with news of Metaforim… especially that is a natural … I am 82 + years old, and have been on it since the late 1990’s. I was diagnosed at that time. I do not want to go on insulin.. also a needle aversion. I am 160 pounds and 5’8″, but would like to get down to 150.. Last year I was up to 192, so by halving my meals, and now with the metaforim idea, I have lost almost 30 pounds. I am also on glimepride and onglaze (sp?). Everyone has told me I am young for my age, which I have attributed to my English genes… wrinkle free skin, smooth and bright, (never smoked or laid in the sun), but now I can think the Metaforim is helping too. Hurrah! My glucose is usually in the range of 120 to 140, unless I have had an injection of cortizone, or other shot- taking meds for infection, flu, colds, etc. then I can shoot up to 290 and higher, which is scarey. I usually drink a lot of water, and walk briskly around the house, plus sometimes take an extra glimepride.

    Knowing what to do for sugar highs would be a helpful article to share with all Type 2 Diabetics.
    Thanks for this article. as ever, Donna

  • Steve

    Just a quick note – I also am on Metformin, 1000 mg AM & PM. But I fail to understand the aversion to insulin. Well, actually I do – I had the same one, until my doc took me off all oral meds, except Metromin and started me on insulin. Best thing that ever happened for control. Lantus at night, Novalog at mealtime, no problems at all. I walk 10,000 steps most days (that really helps!), watch portions and eat pretty much whatever I want – lots of veggies and meat, light on white (bread, potato, pasta, etc). Fasting BS around 110, A1c in the mid-6 range, Type 2 since ’97.

  • Ferne

    I am so tired of diarrhea from taking metformin. Have been told to take my meds after meals to lessen the effects but that is not a perfect cure and I have to try to plan my schedule around the problems with meds. I am so tired of this and it’s depressing.

  • Jane

    I’ve been on Metformin for about 4 years now and have not had a problem. Recently, I waws able to come off the glipizide, but the doctor wants me to remain on the Metformin until my A1c is a little lower. Currently it’s at 6.1 and my daily AM readings range between 85-100.

    You hear so much bad news about prescription drugs, it good to hear some positive news for a change. Thanks for sharing. Jane.

  • Bill from Bluemont….

    Patty, just because YOU have a negative side effect does not mean that there are no ‘Wonder Drugs”…

    Many people have “miraculous improvements” on a lot of drugs that others have side effects. That that you have negative side effects does not mean others cannot get great results.

    I have been back on Metformin for about 4 months after being off it for about 5 years. I had gastric sleeve surgery with a non-adjustable band in August 2005. I lost 130 lbs, and my A1C went from 8.9 to 5.2 over the next year.

    Last winter I regained 30 lbs and had my A1C climb back up to 6.3. That is when I started the Metformin again and last week my A1C is back down to 5.8 and I have lost 19 lbs.

    It is great to hear that this naturally derived drug has more positive news….

  • ed dox

    I wonder who is paying the folks who do these tests and how do they make. I van’t belive this garbage about cancer. It reminds me of a doctor, chiropractic her in DC who claims that he can cure Diabetes 2, and a myriad of other ailments.

  • richard

    I was on glipidize-metformin and actos. I had low spiking so was taken off gllipidize and just metformin. That solved that problem. Then actos was dropped as a lot of side effects with it,even bladder cancer. The dr. added onglyza, a new drug and had a big conflict with metformin. Now on metformin twice a day and seems to control my type 11 diabetes.

  • Reg

    Have been on Metformin for about four years. My A1C is in the 6.3 to 6.6 range. I am only on 500mg in morning and 500 mg at night, I have high readings upon wakening in the morning can be 130 to 150! That worries me, I have told the doctor but he does not seem conerned. I hate taking medicaction but wonder if I should be taking a higher dosage.
    I have lost weight and try to watch what I eat to a point of the doctors say I do not take in enough calories I take in less than a 1,000 a day and weigh 99 lbs at 5 ft 5 inches. I am afraid to eat because I am afraid my blood sugars go up. Again the doctor say ” well we rather you eat and we will adjust the medication if need be.”
    I am like Donna I would like some information as to how to get blood sugars down fast when they spike. I am depressed and feel my quality of life is gone since I have been diagnosed. It seems my days and life consist of carbs, watching others eat and enjoy life and for me restrictions
    The problem I have with Metformin in the begining was stomach upset, and still occasionally get stomach upset but I will cope with it rather than try another medication with other worse side effects or insulin.

  • David Spero RN

    Great comments so far. I’m sorry I didn’t mention the stomach issues and diarrhea. That does seem to be the main problem with metformin. Often it goes away with time, but sometimes it doesn’t. In studies, the extended release form causes 50–80% less diarrhea than the faster-acting kind.

    If extended release still causes problems, and you can’t control the diarrhea with diet changes or OTC meds, that would be a reason to consider stopping the drug, in my opinion. Talk with your doctor about that.

    And Francie, I did mention the B12 deficiency side effect — it’s in the last paragraph. Ed, the findings about metformin preventing cancer are not garbage. They have been documented several times. Of course, you can still get cancer on this drug. The reduction in cancer rates is around 50%.

  • Karen

    I have been taking metformin for about two years; mainly to keep numbers down during the night. I am happy to know it comes from an herb. I had read somewhere that it caused congestive heart failure and was hard on your kidneys, but you are saying the opposite. I am so thankful and it makes my attitude about taking the medication so much better. I am very careful about what I eat and like most need to exercise more. I have to swim for exercise because my knees are very bad. Thanks for the information,

  • Gabe

    In the world of being a diabetic, type 2, it’s encouraging to here some news that may counter some of the high risks and complications you fear when having diabetes, yeah!

  • Indy Guy

    Have been on Metformin for about 5 years. Started with diarrhea, so I cut my dose in half (500mg, once a day), and that has still worked to lower my blood sugars (last 3 A1c’s: 5.5, 5.6, 5.5 – with lots of exercise). I have found that for certain medications, half doses are as effective for me as full doses for others, though I’m a large fellow.
    Also: For diarrhea, sometimes the time-release metformin helps.
    (BTW, Francie, David did mention the B12 issue! Donna, David didn’t say it was natural – but BASED on an old herbal formula.)

    Question: Being that Metformin is both an antioxidant & insulin inhibitor, is there any research on it inhibiting muscle growth, or causing slight muscular atrophy? After all, antioxidants lower inflammation, which the body uses to direct the repairs to the micro-tears in the muscles. Also, IGF-1 (Insulin-like Growth Factor 1) is a major factor in muscle growth.

  • marcie

    For ALL of you who have digestive tract problems with metformin, ask your doctor to let you try one of the extended release forms. They made a real difference for me.

    You might also ask your doctor about trying either Byetta or Victoza. Yes, each of these is injectible, but you don’t feel it any more than — often less than — finger testing.

    I’ve been on metformin off and on — and at various doses — for 13 years. Yes, until I got on an extended-release form, I did have an almost constant stomach ache. Now I take just a bedtime dose so that it helps alleviate the increased insulin resistance that troubles so many with type 2.

    — Patty — I’m sorry it doesn’t work for you, but that doesn’t mean it isn’t a good medication. Using your thesis, then penicillin isn’t a wonder drug either, since some people are allergic to it.

    — andie — There can be some hair loss for some people, but it’s not common. Not to be insulting — I for one am among them — some hair loss is common among older women. Also, there may be be some other endocrine problem besides diabetes that causing the problem.

    — Francie Paper — Yes, B-12 deficiency CAN be a problem after long-term metformin use. It’s a fairly well-known problem. Good doctors check their metformin-using patients’ B-12 levels — if your hasn’t, then requesting it is not out of line.

    — Donna — Your daily sugar levels sound pretty good, especially for someone of your age. No insult intended — with aging, people’s levels seem to go up. Cortisone, illness, stress and several other situations can cause a rise in it, also. When you say you’re interested in knowing what will bring your blood sugar down, do you mean for episodes of high readings or do you mean over all? Check more deeply into it on the web. Truly, that’s where I learned everything about type 2 — I was living in an area where it was the only source, and it’s served me exceptionally well.

    Is your doctor okay with your taking an extra dose of your medication?

  • Diane Fennell

    Hello Reg and Donna,

    Thanks for your comments. You might be interested in our article “Strike the Spike II: Dealing With High Blood Glucose After Meals,” by certified diabetes educator Gary Scheiner, as well as the other articles in our “High Blood Glucose” section.

    Thank you for your interest in!

    Diane Fennell
    Web Editor

  • Mary Morris

    I found out in June of 2010 that I was a Diabetic and my Doctor put me on Metformin right away. I’ve been taking it everyday since then and my Doctor says she’s glad that I’m doing so good with my Type 2 Diabetes. Thanks for the info any way. I’m going to make a copy and give it to my Doctor when I see her next month. Thank You. Mary Morris.

  • Bill Giman

    I am taking Glucophage (metformin), and also using both Homeopathic medicine to control the bad side effects, and supplements like B12 to improve my DM2.

  • David Spero RN

    Bill, can you share what are some of this homeopathic medicines you are taking? Seems like the intestinal side effects are a big deal for many of us.

  • Ange Taylor

    Interesting article! This may explain why I am tired all of the time..the lowering of the Vitamin B12. Guess I will have to be consistent with my vitamin usage!

  • gail beers

    For those of you who are bothered by diarrhea you may want to stay away from milk products to see if that is the problem.You may have become lactose intolerant—that turned out to be my problem. It is worth a try. Good luck.

  • judith blalock

    I AM A 68YEAR OLD WAS DIANOSED WITH TYPE II DIABETESFOUR YEARS AGO HAVE BEEN ON METFORMIN SINCE.I HAD A STROKE IN MY EYE LOST THE VISION NOW I HAVE DEVELOPED GLAUCOMA SO THE EYE DR.HAS ME ON THREE KINDS OF DROPS TWO TIMES A DAY ONE OF THESE IS A STERIOD SO NOW MY READINGS ARE BETWEEN 130 &140in the mornings .but when my a1ccame back it was 5.7which the dr.said was great so i am thinkingthat during the day my sugarsmust be running good .i feel that i am very sensitive to the steriods and that causesthe high readings .would like input on this please.on another note i also have diarea at times but i dont seem to have other problems.

  • Monia S. Turley

    I am very pleased to read about the anti-cancer benefits of metformin (met.) I have been on met for nearly 15 years. I have always had the side affect of diarhea. However, met is truly a wonder drug to me. I am 50 yrs. old and when my doc. discovered I had pre-diabetes, he placed me on 500mg of met. The first two things I noticed was my depression levels weren’t as bad and the best thing of all I ended up with a regular menstrual cycle. I have fought since I was 16 to battle irregular to no periods with polycystic ovaries. I went on birth control (1 yr.) to try to make my body work, and as soon as I went off that drug I had no period. Then the doc put me on prevara–same thing quit working, my last attempt was fertility, again no pregnancy and no periods. (This was before that met was discovered in conjuntion with the drug cyrin on women who were unable to become pregnant to be able to conceive.) I told my doctor what was going on that I was having a regular period. He told me at that time that there was no indication of met doing that. Well, I explained to him that taking the met was the only thing different that I was doing and I started having regular, on time, periods. He asked if he could share with the medical community, and I said please do. Nearly a year later, the announcement was made that met/cycrin was able to help folks such as myself. As to the side effect of prolonged diarrhea, like Marcie above, the extended release really does help. I was on the faster acting for years, and I recently went on the extended release (ER) (now up to 2,000 mgs a day) and it helped. One thing I have tried, since I learned about it from one of Mr. Spero’s articles, where a patient on insulin spread out the ER met and had great results, was to spread the met out every 6 hours. I thought I would try that, even though I’m not on insulin. Not only has it helped slow down the diarrhea, but it has helped to lower my sugar levels better. It is aggravating to clock yourself, but I have had better benefits. Finally, I have had a thyroidectomy which was cancerous (bilateral papillary carcinoma). Having read this article about the benefit to fight cancer, I am inclined to believe that with the my taking met for the last 15 yrs. along with prayer has significantly helped me. I hope my words my help someone.

  • jim snell

    Great news from Monia Turley:

    Taking one large dose only ensures a short interval of very high up to strength in blood of met. The body does NOT re-distribute it out.

    I have run many hourly tests on heart medicine and others and guess what – you need to space around the clock to maintain even drug coverage and effect over the clock.

    I have had this argument with drug company safety officers who finally concede – oh well space it around the clock and why yes maybe taking one large charge does not work.

    I do not know who the nut is in the drug industry
    who thinks stuffing in large charge gets one to long term even drug distribution.

    Metformin (standard) is no different – 2.5 hours up to strength, 2 hours at peak and 1/2 hour exiting for me. The larger the dose, the equation dosen’t change and only gets stronger in blood over same up to strength period – 2 hours.

  • Angela

    Metformin did a good job of controlling by blood sugars — however, I suffered from a real problem with diarreha for 9 years before I started Lantus injections. The very next day – no more diarrhea.

  • Roger

    I’m a newly-reformed type-2 diabetic. I’ve had the disease for eleven years but it’s only recently that I’ve been following a low-carb diet and obeying the rules. For years my A1c would be in the 7.5 range and I’d ignore it (and my doc’s advice!)

    that’s all changed – two months ago my A1c spiked all the way up to 12! I’m now rigorously following a very careful diet, losing weight (245 down to, currently, 216) and my FSB readings are between 90 and 100 each day.

    I now take 2×500 Metformin in the morning and the same at night (2000); I also take two Glipizide XL-2.5 daily.

    My question: To what extent do the meds lower my sugars? Is it by, say 50% or perhaps far less – say 5-10%? I’m afraid to tinker with my dosages without the doc’s approval but is there an answer to my question? Or is it unquantifiable?

  • David Spero RN

    Roger, it’s very individual how different doses of medicines will affect different people’s blood sugar levels. The only way to find out is to try different doses, but I don’t see a reason for you to do that, since your numbers are pretty good now. You could ask your doctor about popping another 500 milligrams of metformin mid-day, if your afternoon sugar levels are high.

  • Roger

    David – thanks for your response.

    I see now that I didn’t phrase my question as well as I might have. I suppose I won’t know for sure how I’m doing on my new regimen (100 carb units per day) until my next A1C which is in Aprail. If that gets me a 6 or less I’ll be happy.

    I’d be happier, however, if I had more ‘wiggle room’ with my meds. Right now I believe I’m at the maximum dose (2000 Met. plus two Glipizide daily) so, should my diabetes worsen despite my best efforts with diet and exercise, the only next step would be insulin. I’m fiercely resistant to crossing that line (for some reason that I can’t pinpoint).

    I know I can try this for myself but I wondered what the conventionbal wisdom says. IF I’m under ‘6’ at my next test, could I perhaps lower my dosages? I must stress that this is the first time that I’ve actually observed a rigid diet – the results (my good Fasting BS)_ are encouraging and they’re keeping me motivated. So is the slow and gradual weight-loss I’m experiencing.

    Currently I don’t test myself during the day – I’m assuming that my next A1C will tell the overall story and that ‘spikes and troughs’ are inevitable – ‘average’ is the key, surely?


  • Carolyn Rountree

    I have had no trouble with metformin drug so far. I just hope it doesn’t get a side effect.

  • Winniei

    I tried Metformin and was unable to take it. I was unable to eat or drink and became dehydrated. I lost about 4 pounds in a weeks time but it was mostly water weight because as soon as I stopped taking it, I gained all the weight back in 3 days. i then took the brand name and was unable to take it.


    I have been on metformin for several years. I still have problems with diarreha. My gastroenterologist suggested that I not take it due to my IBS. I did fine without it, but my A1C was elevated and my primary doctor put me back on it, and the bowel problems started again. So she decreased the dose and I did better. When my A1C was elevated again, my new primary doctor doubled all my meds plus put me on more medication for my diabetes. Not good. Now my primary doctor has decreased some of my medication, which takes care of the very low bs that I had, but she did not decrease my metformin. The colon problem just got too much and rather than fix my dose of metformin, she wanted me to take more medication for my colon to continue the use of the metformin!! I got tired of not being able to go anywhere or afraid to go any place because-what if I couldn’t find a bathroom!!!
    So-I decreased my metformin,( you know what they say about nurses!!), I’m not taking near the colon medicine I was but I still have a problem with my nose running. That I can handle.
    I will see her in a couple of weeks, and am hopeful she will listen to my problem and let me take the metformin once a day..Plus my daily fingersticks are in a good range. But I know the A1C reading will rule out!!! I am on my fourth type of injectable, which this one works really well..

  • Becky

    When I was first diagnosed, I used metformin. It did nothing for me except cause low glucose after exercise. The doctor increased it to 2000mg a day, still nothing for lowering my glucose levels. Then she put me on insulin 4 times a day and had me quit the metformin. That worked. My diagnosis was changed from type 2 to 1, but I don’t really have type 1 either. Maybe I should take metformin again for its other benefits.

  • Phyllis Henderson

    I took this drug when I was first diagnosed with diabetes Type 2.
    Unfortunately, I soon developed diarehea! Just a year ago my doctor once again tried to start me on a mix of a drug with Metformin in it, the same thing happened, horrible diarehea!
    I now don’t take it, am on Glipizide 1 tablet twice a day….it seems to work for me.

    Am happy for those who do not have this side effect.


  • David Spero RN

    Roger, 2000 mg day is common for metformin — you can go up to 2500. But diet and activity are more important than meds for diabetes, so keep doing the good things you are doing, and see what the numbers are.

    Winniei and Carol, sorry metformin is so hard on your stomach. Winnei, you were certainly right to stop taking it. Carol, I’m against letting the doctor put you on a med that makes you sick. Maybe ask her what else you can try, if metformin has too many side effects.

    Becky, your story of being misdiagnosed as Type 2 is common. I blogged about it a few weeks ago.


  • Roger

    That’s a fascinating ‘link’, David – it proves what a minefield all this can be!

    My diabetes was, I was told, brought on after several bouts of pancreatitis, the last of which (2001) resulted in a five-week stay in hospital with pseudo-cysts. The pancreatitis could have (they said) been due to thiazide-based diuretics (I’ve never been much of a drinker).

    Thank you very much for your responses; they’re much appreciated.


  • Doris

    I tried Metformin , had such a nasty reaction to it, I stopped it !! It gave me unbelievable stomach pain, dizziness, nausea , and worst of all , it made my tongue swell and my lips felt “fuzzy”. Good luck to those who can take it , I will keep on with my Gluconorm because the other Diabetic oral meds are sulfa based and I am allergic .

  • Mary Lou

    For anyone that is able to take metformin, great. I was on it for two weeks of pure hell. I have never been so sick. Oh, you will get use to it. Never did. I had nausea and diarrhea for the entire time. Fortamet I can live with, metformin no way. Janumet was the same problem.

  • Ben Wood

    I took Glucotrol for many years. The doctor increased to amount but I had little control over my glucose. Excercise had much more effect. In January of this year my present Doctor added Metaformin and another med Levoroxine(sp)my glucose has been normal or near normal levels for two months now. I am a type 2 diabetic and happy to think that I may avoid all the horrible compliaions of dibetes. Talk to your doctor about metaformin.

  • Geri

    I have been on metformin (2000 mg a day) since September 2011. Initially, the doctor prescribed it in 500 mg. tablets. So I took 2 after breakfast, and 2 after dinner. It took me 1 1/2 months to adjust to the medication. I had diarrhea, and if I didn’t eat enough, a tummy ache. Even with the decreased usage as I was adjusting, my fasting blood sugar went from 120 to 103. I also have the dawn effect so metformin seemed like the right medication. Now that I have adjusted to the medication, he has changed me to 1000 mg pill in am, and 1000 mg pill in pm. I am pleased that my fasting blood sugar has gone down. My A1C has not changed – 6.1. Sometimes I would spread out my morning dose to 500 mg. after breakfast, and 500 mg. after lunch. With the higher dosage pill, I won’t have that luxury. Will dosage all being in one pill twice a day make a difference?

  • catherine V E

    I’ve been on Metformin for many years. 1500XR daily. Recently the dose had to be reduced due to early kidney failure. Elevated BUN and creatinine. How common is this?

  • Linda


  • David Spero RN

    Catherine and Linda,

    Well, no drug is right for everyone, and metformin isn’t, either. Stick with the lower doses and try more physical movement and perhaps eating better if you can.

  • latisha

    hello everyone metformin is a wonder drug for me been doagnosed with diabetes type 2 in 97. i also suffer from polycistic ovaries…i could not get pregnant because i was not ovulating i was on 500 mg a day for 2 weeks and was pregnant i had two chldren unfortunately my first baby passed away at 1 month from meningitis!



  • Peter

    My doc just put me on metformin transdermal. No problems with stomach upset. You just have to have a compounding pharmacy make it up for you.

  • Guy

    Everyone complaining about diarrhea do not understand how the drug works.

    Its trying to rid your body of those sugars, the ones sitting in your stool, it’s trying to get rid of.

    If you REDUCE YOUR SUGAR and/or FOOD INTAKE, you’ll find the diarrhea goes away. If you change how you take it, you’ll find the diarrhea goes away.

    If you take beta blockers, it kills the effectiveness of Metformin. Try everything else first for blood pressure control.

    The urge to go to the bathroom is the indicator you must use to know (along with testing) that you’re on track with your blood sugar. On Metformin, If you gotta go poo right now = your blood sugar is too high.

    Wonder drug indeed!

    • Forgivensinner

      I have low blood sugar and I am on a stict ketogenic diet and I am having the bathroom issues. I also only take it with meals.

  • Christina

    I solved the stomach ache problem by crushing the pill (Not XR) and putting the powder in a capsule.

  • JEAN

    I have been diabetic for years and had it under control by losing weight. I went to Dr’s in 2009 and my AC1 thing was 9 he gave me prescription for Metformin then and it gave me such stomach issues i stopped taking it.I just went back to Dr’s a week ago and my AC1 is 9.1 so im back on the drug again.My stomach hurts and have diarea but my blood sugars have already dropped ALOT!Down to 185 after a meal today!Everyone tells me that in time the stomach aches will go away so i’m going to continue taking it and see what happens..I wish everyone well!

  • Esmeralda Mollineau

    I am glad to hear that medformin is something good i have been taking it for three years first 500 mg morning and 500mg night and in a doctors visit in goergia am from the Virgin Island the doctor in goergia toll me i should be in1000mg morning and a 1000mg night i can’t conplain because i take it with food and it doesn’t make me sick i also take cinnamon and for the last 2yrs my sugar level at 5.60 i also lost over 100 pounds that helps but now that i know is for for figthing cancer i want to take it i want to keep looking young my mother side of the family died from conplication of diabetis am 53 and i look 10yrs younger my father family died in the 90’s and 106 !

  • Nicki S

    I was diagnosed with PCOS in March of this year. I take 2000mg of Metformin daily. 1000 a.m and 1000 p.m WITH MEALS… That is the KEY. If you take on empty stomach, you will pay for it!
    Otherwise, I’ve had no problems and it helps.
    However, I was just diagnosed with breast cancer last week- so, the talk now begins on if I’ll stay on it or quit for the treatment of my cancer. No family history and I’m healthy, a runner and only 38 years old. Please, if you suffer from PCOS and are insulin resistant- do your monthly breast exams- it could save your life. My doctor found my mass early- I’m blessed to have such wonderful doc.

  • richard

    I was diagnosed with type 2 in October 2012 with an A1C of 8.0 I’m on 1 500mg of MetFormin along with losing 30 pounds, diet changes, & daily exercise and strength training. I have another A1C scheduled for this month. My meter says i’m staying between 90-145 pre and post meal. At first Diabetes felt like a curse, but now it feels like a blessing in a strange sort of way I guess. It forced me to take care of myself & i’ve never felt better. The best of luck to everyone.

  • eugene murry

    I were diagnosed with type 2 diabetes in july of 2012. Last month my doctod prescribed metformin (1000 mg), and insulin injections (32 units. Why is both medications needed?

    • Superhero

      Sometimes one is not enough to keep your sugar down to a level that is safe.

  • mykal

    I second that Richard. I was dianosed with type two in nov 2012. A1C was 12.5 and blood sugar was 289. What i felt was a curse has put such a fire under my butt that i workout everyday (feels great) and cooking good foods are exciting again. all the efforts have reduced my blood sugar to average range of 106 to 115. lost 35 pounds and hope to reduce my metformin from 2 500mg a day to 1. when i go back to doctor i hope my A1C will drop enough to go medication free.
    I wish everyone going through this much success in controlling this disease.

  • David Spero RN


    You will have to ask your doctor why he prescribed both. You could ask him about starting the metformin and following that for a month or two to see if the insulin is still needed.

    Please cut way, way down on starches and sugars. That way, you’ll need less insulin and may not need any. Also consider a spoonful of vinegar with or before meals, and at bedtime. Read the vinegar articles on this site.

  • blake

    i refuse to take it i would take it its a black box warning u no mertaformin causes lactate acidois which is fatal in haslf the people who have it so if it did not have this issue i would take it type 2 should never take insulin try this site wwwmercola,com instead of depending on your doctors so much people should serch this and any drugs side effects if u all no actos causes bladder cancer your a fool if ull still taking it there are many natuaral approaches like chinese medicine been around 5000 years good heath to all

  • pam luce

    I was recently diagnosed with type 2 by accident, went to er for difficulty breating and chest pains, they did numerous tests and said i had copd and bronchitus gave me scripts and sent me home, 20 minutes later the er called for me to return to hospital stating dr wanted to talk to me. So I returned they threw me in a bed with out so much as a word and said the Dr will be in. When he finally came after 20 minutes of wondering “what is going on” He tells me that I have diabeties. My family has no history of this so I was baffled I am 52 yrs old , 5″1 normally 115 lbs and after being sick with the bronchitus , I dropped down to 100. Anyways i was hospitized for 3 days cuz my ac 1 was over 800 for 3 months. I was put on januvia and metformin but had to stop the januvia cuz it cost 250.00 So I remained on the metf.500mg, after 2 months it started to irritate my stomach to the point where the smell of food made me nausus, constant bathroom trips and I dropped to 85 lbs. So my dr then switched it to metf ER 5oomg 4 times a day.It been about 2 weeks now and it’s starting to do the same with irritation etc. This is so frustrating especially when no family history and Im not a big snacky -sweet eater.

  • pam luce

    oh my ac-1 was at 13 , got it down to 9.

  • David Spero RN


    If metformin is tearing up your stomach and not helping all that much, you must ask your doctor what other meds you can take, including insulin. With such a high ACc at such a thin weight, I would suspect you may have LADA or MODY and might not be producing much insulin. You can find articles about LADA and MODY on our site.

    You might also consider nondrug approaches like vinegar, bitter melon tea, and a low-carb diet. These often work better than medications. We have written about all of them on this site.

  • Thomas

    Hi everyone, Metformin has helped me greatly, In the beginning I had the GI problems, but i have found now that as long as I have a good meal, I’m okay.
    I made the mistake once of taking my pill planning to eat right away, got side tracked by a Phone call.
    I will never do that again! I suffered all night!
    Everyone responds differently, but I take a B12 subliminal, everyday with my ALA, Q10,and my multiple.
    I would say for those that can’t tolerate the large dose maybe with your doctors advice try taking a smaller amount first before you give up on it.
    I am 63 retired Medical.

  • Kopi lim

    Hi, I am new to this site but I am very thankful to find this website with so many sharings. My mum was diagnosed with diabetes recently and the doctor suspects that she has diabetes since 2 years ago because her glucose level is more than 13 mmol/L.

    Now she’s taking metformin, only two dose per day. She will take her medicine once after breakfast and once after dinner. But her glucose level is not so stable. Sometimes it’s around 7.5 to 8.7 mmoL/ L but sometimes it goes up to 12, which is pretty stressful for herself and family members. She’s been eating very little and it’s quite disheartened to see bad readings sometimes.

    I was pretty worried about kidney failure because I didn’t want to see her going for dialysis every week.

  • Jm

    I was been on metformin since July of 2011 when my doctor gave me the news that I was type 2. I have a a1c that has been at 6.0 for the last 9months with a glucose level of about 110. I did pretty much what my Dietician told me at the time of my type 2 news. My weight has gone from 205 down to 175 on a 6 ft frame and I never felt better!!! I have had no bad side effects from metformin and it has given me a new lease on life!!! Whole wheat bread and pasta tastes much better than the refined garbage than I was eating before and is much better for my health!!! My eyesight improved immediatly after starting metformin along with the change I made in my diet immediatly after finding out I had type 2. Besides having a good doctor, I also see my foot doctor once a month just for preventive check-ups.

  • Jm

    Add on: I only take 500mg once a day.

  • Mary

    I took metformin for awhile but it made me so tired all the time. I felt like I was drugged up. As soon as I got off of it I seem to feel awake! I wonder if the 250mg am was because I was not use to it. It did bother my stomach a little. I got great sleep at night that was for sure. May try the ER version and see if that helps. For now I am on the insulin. Any reason why it made me so tired and sleepy all the time????

    • JL

      Everyone who takes Metformin will have initial stomache and diarrhea issues that should go away as your body adjustscto the meds. It is also important to take metformin with or just after a meal to help prevent these issues.
      As for the sleepiness, have your doctor check your vitamin B & D levels. Metformin may be affecting your absorption of these vitamins, and low levels can cause fatigue.

  • Monday Ogboloko

    Thanks for this great information, but what eyes and ear whishies to see and hear is the final cure to this deblitating sickness, that makes some one unhappy always and contious live long intake of drugs daily.

  • zoya

    Metformin is a very beneficial drug. scientists have found a lots of benefits of it. it has been evalusted that it reduces the risk of breast cancer. But a very recent research conducted has found that metformin got no benefits for non diabetic patients with high risk of cardiovascular disease.
    here is the link to the article

  • Rhonda

    There are some very interesting comments here. I hope who ever made some of them reads mine. The people who are having morning highs…eat some protein before bedtime. I usually eat a piece of toast with peanut butter. There was one person who was only taking in 1000 calories a day, her doctor was right she need to eat more. I go by the rule of 45 carbs per meal(40-50) and I follow this at least 80% of the time, but only splurge for special things…the occasional candy bar(love dark chocolate) or homemade bread pudding, but make sure I ride my stationary bike when I do. For the B12 issues, take a subliminal, goes directly to the blood stream(metformin cause the oral type not to be absorbed). I was diagnosed 1 year ago…a1c was 14.2, now I have it under control 6.0, I have to agree with others on here I first I thought it was a curse,now I think it is a blessing, I’ve lost 30+lbs…people say I’m skinny

  • M.D.R

    Metformin is sooooo good I threw it in the trash! 😀 haven’t looked back. Not taking Januvia or Janumet either.

    You want to feel good and live with Diabtetes, then excersize and diet folks. Sometimes I think Diabetes meds are worse than the disease!

  • Allan Silliphant

    I have had type 2 diabetes for 14 years. I also have atrial fibrillation, and recently had very
    successful right carotid artery surgery, which
    has helped my general health greatly. That surgery
    permitted laser eye procedures, which allow me to
    see well without glasses. This choice has greatly
    improved my overall sense of well being. I am a 73 year old male, a bit shy of 6’2”, weighing 205 lbs.I walk fast without shortness of breath. Regular Metformin gave me serious GI tract problems, so my VA Dr. switched me to the slow release version, called SA. That allows me to take 2000 milligrams daily with no distress. I also taken the whole gamut of anti-oxidents, such as AstaXantin, Krill oil, fish oil, CoQ-10, and use diatary coconut oil with oatmeal, and whole grain breads. PubMed(USpubH)has announced that the red-wine molecule Reveratrol helps to decrease synergistically the insulin resistance that Metformin is so well known to address. They say evidence suggests that both can compliment eachother. I’m hopefull, and getting stronger each month, expecting to be around in my 90s or
    better…Metformin rocks in my opinion!

    • Claudia

      Wat brand fish oil do you take?

    • Claudia

      Hi Allan. Which fish oil brand do you take? I can’t seem to find a good one

  • Anita

    Metformin has magnesium in it, that’s why it causes diarrhea. Magnesium is a good for a lot of maladies, but it is hard to take because of the diarrhea it can cause. Google magnesium, you will be amazed.

  • Camelia

    I have Type 2 diabetes and I am 84 years old. My prescribed daily dosis is 2,500 mg of Metformin, but I was told that this amount is very risky due to my age. I have been taking instead 2,000mg of Metformin daily and I have now ups and downs in my sugar levels, which I didn’t have before.

    • David Spero RN

      Camelia, you might want to talk that over with your doc. It’s true that older people have to be careful about large doses of metformin because their kidneys don’t work as fast to clear it out. But that might not be true in your particular case. If you were doing better on 2500, you might ask if that would be OK to resume.

  • Claudia

    Hi everyone just new to this site. Started metformin but am really scrd it will cause harm. . Is This a safe drug? Any help would be so great

  • Charlotte Jane

    Hi im thinking about taking metformin but im pretty healthy i dont have diabetes or anything should i go on it i have pcos amd the doctor told me to go on the pill and lose weight but i just want a second option please

    • HI Charlotte,
      Many doctors prescribe metformin for PCOS. It seems to help a lot of people. What do other readers think?

      • Sherry H

        Yes it does help with PCOS, i have had PCOS for about 6 years and just started metformin about 2 months ago, it helped get my period back and also helped me lose weight (which is a big thing for PCOS), I am going to try having a family soon, hopefully it works 🙂

    • Rachel

      Hi, I’m 15 and I have PCOS too. I had awful awful side effects from birth control so now I’ve been on metformin for about two months and it’s incredible. I’ve lost ten pounds without trying at all, and I adore the drug. I feel great!

      Highly recommended.

  • kathy

    I have type 2, and was just diagnosed with A/fib, is it ok to stay on my metformin ?

  • Ubermensch

    You misunderstood the anti aging effects of metformin completlely. Metformin produces slight oxidative stress in cells – so it is exactly the opposite of an antioxidant. The cell stress triggers some reactions so subsequent cell formation produces stronger cells. There you go, now correct this nonsense of yours.

  • Robin Rodal

    metformin, according to Wouter de Haes, stress the cell with ROS. then he state that is why the metformin an anti ageing drug. following that some people would say that taking vit C+metformin will blunt the effect.
    but i think i understood that it is the sugar regulation which make metformin efficient, not the moderate ROS stress induced.
    taking anti oxydant and metformin would negate the good effect? hard to believe, in my opinion.
    if moderate ROS do good to the cell, why smoke a little bit, eat a little bit of junk would not have the same anti ageing effect? is there not enough ROS intake in our stressy life of everyday?

    sugar regulation or ROS benefits? or both/something else?

  • Roben

    My husband has been battling with pre-diabetes for several years. In early 2012 he had a FG (fasting glucose) of 120 and was 250 lbs (6’3″). He got on a low-carb, high-fiber, low-sugar diet and daily exercise. He lost almost 15 lbs in 3 months and dropped his FG to 110. One year later he dropped another 15 lbs and had a FG of 106. One year later (2014) at the same health wt (220 lbs) his FG went up to 114. One year later (still same wt with same diet and exercise program) had a FG of 115 and in Jan. 2016 at a weight of 218 lbs had a FG of 117. He just started on Metformin 500 mg/day 12 days ago. He has a follow-up appt in 3 months with his physician to see where his levels are at and to test his A1C (for the first time). Interestingly enough, he had a post meal glucose test in July 2015 1 hour after eating a bagel and had a FG of 126 (which didn’t seem that high to me 1 hour after a high carb meal).
    So far he has been tolerating the Metformin really well. No additional weight loss yet and we don’t have test strips so I don’t know yet how well it’s working but I am very hopeful. I have heard very good things about Metformin both in terms of its ability to lower glucose levels but also it’s heath enhancing and anti-cancer attributes.
    Do any of you have any suggestions? We have tried all kinds of supplements and lifestyle changes to no avail (other than the initial improvement 3 years ago). Have any of you experienced high fasting glucose levels with normals glucose levels after eating?
    Thanks for your help and input!

    • HI Roben, my advice would be to not worry so much. Your husband is doing OK. There are other things you could try, such as bitter melon, vinegar, cinnamon, or higher fiber, but don’t stress about it. The metformin will probably help.

      • Roben

        Thanks David. I really appreciate your response. I am hopeful that the Metformin will help a lot. I realize his numbers are not that far from normal so I will try not to worry. I would just like to see them move down instead of up. I will let you know his improvement after being on Metformin for 3 months. That might help others that are pre diabetic and are having trouble getting their numbers down with lifestyle changes alone.

    • Paul Parmele

      B12 shots once a month or every two weeks, taking Pyruvate before meals and possible B12 instant dissolve tablets under the tongue.
      But he needs to ask the Doc and be monitored by your doc or a Bariatrics Doc.

      Now for sure take a Multivitamin and Melatonin of 5 mg before going to bed.

      I’ve lost over a 100LBS IN 8 MONTHS but it slows down or levels off. So recently I lost 10 more lbs. At the beginning I weighed a painful 398 lbs which crept up on me in 2 Years. But now Happily I am at 277lbs, I need to loose 60 lbs. I feel FANTASTIC being HAPPY and HEALTHY.

      PLEASE talked to your doctors before taken this venture to make sure none of your present meds won’t have a Bad Reaction.

      Blessings Be with Blessed Healthiness 🙂



    • mary koppe

      120 after eating a bagel? All those sugars you posted are NORMAL range. I’ve been diabetic for 20 years now.Not certain why the doctor put him on metformin…perhaps for weight loss. It works if you’re not taking insulin.No,never higher glucose levels after eating for me. Is his dr certain he’s not hypoglycemic?I cannot believe they put him on meds without testing his a1c levels. I’d go to another dr,that’s not right. Normal sugar range is under 125 I believe they say now,used to be 135,so they can’t make up their own mind,lol.

    • Thomas Bogardus

      We’re are u all from a fasting sugar of 114 isn’t bad as a type 2 I would be thrilled to have it below 120 fasting as that means u are not diabetic

  • Paul Parmele

    Awesome! 🙂

  • Butters

    Diabetes Self-Management, please tell me if you have received ANY money, whatsoever, from Metformin manufacturers because I have been trying to get my diabetes under control through diet and exercise, managing to follow a zero bad carb and grain diet, much like a Paleo diet, for 3 months now but I am so weak I can’t exercise presently which leads me to believe the blood glucose isn’t going to my muscles for strength. Or I am not drinking enough water and am dehydrated, was told drink 3 – 6 litres/12 – 24 cups a day but I only manage 6 – 8 cups, this might be why I’m weak, dizzy, etc. I’m contemplating taking the metformin but a recent news report said studies showed it did not prevent complications of diabetes which you are claiming here. So please tell me are you receiving money from them ?

    • Butters, sorry you are having such a hard time. There is no “them” in metformin — it’s generic and is produced by different manufacturers around the world and sells for roughly 5 cents a pill. Please ask your doctor why you are so weak. Six to eight cups of water a day should be enough for most people.

      • Wayne Taillefer

        I’m diabetic. When in the hospital and unable to eat for weeks it was discovered that I was dehydrating even with regular fluids. 1/4 Gatorade was added to my fluids. I am one of the people who must have some sugar intake with my fluids, or they dont hydrate me as well. ( I thought so before this ) watered down, regular Gatorade is a normal “go to” for me now. It has little or no effect on my sugars. And No I have nothing to do with the makers of gatorade !

  • Mary Avis McCullock

    Hello. My name is Mary and I was just diagnosed with type 2 diabetes a week and a half ago. I’m 32 years old and have been struggling with weight issues and pre-diabetes since forever. I started on 500mg 2x a day and they’re bumping it up to 1000mg 2x a day since my A1C is 10.6. It gives me some stomach issues, but overall it’s worth it! I have more energy than I have had in the past year and I’ve already lost 5lbs since starting! I’ve always eaten pretty healthy, but since I have a pre-disposition to diabetes (pretty much everyone in my family has it), my body succumbed to the disease. After reading this article, I’m very pleased my doctor put me on this medication – the good this medication does is phenomenal. I can’t wait to see where I’m at during my next visit!

    • Favi Albiar-cruz

      i was just diagnosed Friday and same problem as you even though i was eating healthy it runs in the family.
      feeling bummed about this.

  • dini

    Just stepped into the pre diabetic spectrum. My Fasting are any where between 100- 120 and that too after having oats and an apple at nigh. After that starts a intensive 2 hour exercise and would normally eat breakfast. Post readings shows from 130/140 and rarely 180. Why is this ??? after an intensive workout and a nominal breakfast? The after having lunch the twist will come , usually have with beef/Chicken/ Fish. Post readings is now 110 to 130. Man i dont understand this. Why mornings are high only? Watching from a video suggestion i ate 1-2 eggs (White only) after exercise and before breakfast. Damn!!! it is now low 120!!!
    Can anybody advice what is happening? is my body producing sugar naturally? BTW im 38, having fatty liver and cholesterol.

    • Hi Dini, Can’t be sure what’s happening, but you might be going too low and rebounding. Bodies don’t like to go low and will put out extra glucose to get your level back up, and sometimes overshoot. If that’s what’s happening, metformin would probably stop it, but you might not want to stop it, because of risk of lows. Ask your doctor.

  • M. Valentine

    Your link, “Reasons to Live,” Yeah, it ain’t working right. It takes one here:
    Check it out.

    • Madavor Media

      Thank you for alerting us — that link has been removed.

      Diabetes Self-Management