One of the Most Effective Diabetes Drugs

You may recall that I recently wrote a series on various medicines and how they can affect your diabetes (see "The Ups and Downs of Meds and Diabetes [Part 1]" as well as Part 2, Part 3, Part 4, and Part 5). One kind reader, who happens to be a nurse, asked me to devote a post to metformin with regard to its effects on kidneys and special considerations to keep in mind with this drug.


I wrote about metformin back in December 2006 (was it that long ago?) and its link to vitamin B12 deficiency (see “Metformin and Risk For Vitamin B12 Deficiency”). But there are other important facts to know about this very popular diabetes drug.

Raise your hand if you take metformin. OK, obviously I can’t see you, but I’ll wager that many of you reading this are on this medication. Metformin is the generic name for Glucophage, Glucophage XR, Glumetza, Fortamet, and Riomet. It also comes combined with other diabetes medications, including glyburide (in Glucovance), glipizide (in Metaglip), rosiglitazone (in Avandamet), pioglitazone (in Actoplus Met), sitagliptin (in Janumet), and repaglinide (in PrandiMet).

I’ve read that approximately 35 million prescriptions were written for metformin in 2006, making this one of the top 10 best selling generic drugs. And you may not be aware that the American Diabetes Association, in its 2006 practice guidelines for health-care professionals, recommended metformin over sulfonylureas as the first drug of choice for people with Type 2 diabetes. This really isn’t surprising. Metformin has a long track record for being safe and causing relatively few serious side effects—plus, it also works! Chances are, if you have Type 2 diabetes and need to start on medication, your health-care provider will recommend you take metformin.

How It Works
Just a quick review in case you’re not sure what metformin does. Metformin works by:

  • Reducing the amount of glucose released by your liver (and your liver regularly releases glucose); and
  • Helping the insulin in your body work better (i.e., increasing insulin sensitivity).

Metformin doesn’t cause your pancreas to secrete insulin, as do sulfonylureas, so it’s very unlikely that you will experience hypoglycemia (low blood glucose) with metformin alone; however, if you take a sulfonylurea or insulin along with metformin, you may get hypoglycemia.

Side effects are usually temporary, and consist of gas, nausea, vomiting, and/or diarrhea. Some people have side effects, some never do. And if you can “stomach” metformin for the first month or so, you may end up losing weight (another benefit for many people).

Metformin isn’t meant for people with Type 1 diabetes, although it has been known to be given “off label” to people with Type 1 who also have insulin resistance.

Things To Keep in Mind

Lactic acidosis: Lactic acidosis is a rare but extremely serious condition that occurs in about 1 out of every 30,000 people who take metformin. Symptoms include weakness, shortness of breath, abdominal pain, and muscle pain. People at increased risk for lactic acidosis include those with kidney or liver problems, congestive heart failure, alcohol abuse, or dehydration. Lactic acidosis may also occur if metformin is taken during X-rays with dye and surgery; for this reason, metformin usually needs to be stopped 48 hours before these procedures. Always talk with your health-care provider if you take metformin and are scheduled for an X-ray, CAT scan, or for surgery.

In addition, metformin should not be used in people with a creatinine clearance of less than 30 ml/minute, and used with great caution if the creatinine clearance is between 30 and 50 ml/minute (creatinine clearance is a test that measures how well your kidneys are working). So, if you have diabetic kidney disease, metformin may not be the first drug of choice for you.

Irregular menstrual periods: Metformin is used to induce ovulation in women with polycystic ovary syndrome (PCOS), a condition that can lead to an irregular menstrual cycle.

Gestational diabetes Metformin is now deemed to be safe in women with gestational diabetes. Women with gestational diabetes traditionally had to take insulin during their pregnancy. Metformin (and also glyburide, brand names Micronase, DiaBeta, and Glynase), are now two other options.

Prediabetes: Although not formally approved by the U.S. Food and Drug Administration (FDA), metformin has been given with success to people who have prediabetes, and, in fact, was used in a major study called the Diabetes Prevention Program to help prevent diabetes.

Children: The incidence of Type 2 diabetes in children is escalating, and while, of course, lifestyle changes are critical, metformin should be the first drug of choice, if indicated.

One of the physicians I work with calls metformin the “best medication for treating Type 2 diabetes.” So, if you are one of the many who take metformin, I hope that’s the case for you!

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  • grammasmiles

    I have type 2 diabetes and have used metformin 500mg for years without any problems. But this past year I started to have higher blood sugar levels so my doctor gradually raised the dosage to 2000mg a day and it seems to be working fine again.

  • sh10492

    I found for many years that Metformin was very effective in controlling my glucose. I did experience some of the side effects listed above.

    As a follow-up to the 2006 article re: B-12 Deficiency, I am finding many long term users are experiencing fatigue. Whether or not they have developed pernicious anemia, I don’t know. However, B-12 has been effective for most.

    Pernicious Anemia is serious stuff. Back in the day (way back)it was a fatal condition.

    In December, 2007 I was taking Actos, 200 mg of Metformin,and 70 units of Insulin per day. Withing 5 weeks after starting B-12 supplements, I was off insulin (as in ZERO)and Actos.

    I am now down to 750mg of Metformin. Still a very good med but please, PLEASE ask you Doc for a CBC to check your B12. It is not a normal part of your A1C protocol.

  • mr.fff

    metforom works great for me i have type2

  • Raccary

    I used Metaformin for years and it always worked very well on my type 2 diabetes.
    Then out of the blue.I started have diarrhea, then uncontrollalbe diarrhea, at times unable to leave the house.
    I finally had to stop taking it for this reason.
    It was back to Insulin for me as no other oral medication ever worked as well as the Metaformin.

  • Mike

    Interesting options for the survey. What about those who used to take it for Type 2 diabetes and found it did not help and are now on insulin?

  • Tara Dairman, Web Editor

    Good point, Mike–I didn’t think to include an option for having taken metformin in the past but not anymore. I guess that the closest response would be “No, I have Type 2 diabetes and do not take metformin,” though that certainly doesn’t tell the whole story.

  • CalgaryDiabetic

    Dear Tara. The survey should include an option that I have tried but had to quit the drug. Many people get quite sick on it.

  • Kris

    I, too, am on Metformin after diet and exercise alone didn’t lower my blood sugar. My question is this: which is the best way to take metformin, with or without food and are there any specific times of the day to take it? I take it twice a day and have been told just to take it twice a day at any time of the day. What do you suggest?

  • budgetboy

    I’ve taken metformin for many years. First by itself, then with glyburide. At first it made me nauseous and had other side effects. Gradually those went away. Now I don’t notice any side effects. When I started my new diet and exercise regimen I began to have frequent hypoglcemic episodes. So, my doctor stopped the glyburide and now I take only the metformin. My A1c is down so I don’t have to use anything but the metformin.

  • RBD

    I have type 2 and take 1000mg Metformin in the am and 1000mg in the pm. In addition I take 50mg Starlix before each meal and this combination works perfectly for me – provided I remember to take the Starlix each time.

  • mary

    My husband has type 2 diabetes and just recently started having a lot of diarheaa.He was diagnosed last year and was put on metformin.He is still on it plus glimeperide now as well.He takes the metformin twice a day and a half pill of the other twice a day.Can this be the cause of his diarrhea?Other than that he seems to be doing okay with the diabetes its just that the bathroom going all the time concerns me.


    I was DX-d with Type II Diabetes in May of 2008. However, I had it a lot longer than this. The symptoms were all there but my primary doctor never took me serious.

    On Feb 21, 2008, I fell and broke my wrist. The paramedics measure blood glusos and asked me if I was diabetic, I told them “NO, I had never been diagnosed”. My blood sugar count was over 400….

    When I finally got DX’d, the doctor RX’d me Medformin 1000 X twice a day.

    So far, so good.No more side affects than I already had.

    I have Fibromyalgia which mimics diabetes.

    I had part of my right lung removed in 2004, it was cancer, but thank God, I was cured of that.

    When I was told I had cancer, I was calm, no big deal…I would either get well or die.

    But when they told me I had diabetes, I went into shock, remembering all the horror stories about diabetics losing their digits and or limbs or having to take all kind of treatments etc…i.e. kidneys.

    So yes, the Medformin is saving me a lot of grief, I am just glad they have a medicine that works

    Maybe this was more then y’all wanted to know but I wanted to share with you , how much better I feel now since I am on Medformin.

  • Bahamut

    I’ve been using metformin and so far it’s the best drug out there.

  • acampbell

    Thanks to all for sharing your thoughts and stories. Sounds like, for most of you, metformin has been a big success! Also, I wanted to add that vitamin B12 deficiency is a definite issue for long-term metformin users. This isn’t measured in a standard CBC blood test, so it’s worthwhile talking to your healthcare provider about this and whether you should have your B12 level measured. This would also be a blood test separate from a CBC.

  • LAW

    I am seventy and have been diabetic since the mid-1980s. I have been on insulin since 1995. I had taken metformin for years but in the past couple of years, had to stop taking it because of severe intestinal discomfort. I have IBS, and this aggravated it considerably. For the first few years I was on this drug I took the original Glucophage and got along fine. I began having problems when the prescription was switched to generics. I have had similar problems with other drugs. Something used (perhaps in the base) to make the generic drug seems to be causing the problem. My medicare supplement will not pay for the more expensive glucophage, so I have just increased my insulin and no longer take the oral drug. I can’t help feeling that the pharmaceutical and insurance industies are ruling our lives.

  • carolena

    I’ve been using metformin for about two years and have not had any problem with it. The drug that gave me all the problems was Actos.

    • Carl

      Actos thought me to a hospital with a heart attack, thanks God I am still alive.

  • acampbell

    Hi Kris,
    Metformin is intended to be taken with a meal, so if you take this twice a day, you’d likely take it right before you eat breakfast and then right before supper. The extended release version of metformin is taken once a day, usually with the supper meal. However, it’s a good idea to check with your physician as to the best time for you to take metformin.

  • acampbell

    Hi Mary,

    It’s possible that the metformin is causing his diarrhea. However, there are many other causes of diarrhea, ranging from bacterial and viral infections, to parasites, to food intolerances (such as lactose intolerance, celiac disease), to intestinal disorders (Crohn’s disease, ulcerative colitis). I’d suggest he talk to his physician about this. Perhaps he can decrease the dose, temporarily, to see if this makes a difference.

  • Joan

    I have been on Merformin 500 x2 for 3 years. The first year I lost 75 lbs. and have maintained that weight for the last 2 years. Also at the end of the first year my a1c was 6.0 and is now 5.1 I have been very satisfied with the way metformin has worked for me.

  • MzizGayle

    I am also on Metformin. I take the Extended release version and the side effects are practically none. The regular metformin did give me the stomach distress horribly, in fact I dealt with it for almost 6 months.

    I was handling with diet and exercise for years but ened up with Metformin and it controls the highs and lows much better and helps keep me in the range my doctor and I both are comfortable with.

  • ColoradoSprings

    Hi Chris & Acampbell
    Regarding when to take your Metformin, actually a diabetic nurse suggested I take mine (2 500 daily) in the evening before I go to bed I have done this for about 7 years and my A1C is 5.2.

  • acampbell

    Hi ColoradoSprings,
    Thanks for sharing. It can make sense for people who take metformin to take most or all of their dose in the evening, especially if their fasting glucose levels tend to be high. The liver tends to put out more glucose in the early morning hours, so this is the perfect time of day to have metformin on board. It’s a good idea for people who take metformin to talk with their provider about the best time(s) to take their doses.

  • marcie

    Re: the concern about the risk of lactic acidosis associated with using metformin.

    Perspective is an important factor in evaluating this risk, which seems quite small.

    It has been published in several studies that death from lactic acidosis is higher among those who do not take metformin than among those who do.

    In references below, please note that those portions within { } are my comments.

    Classification of Some Causes of Lactic Acidosis (Cohen & Woods, 1976) {Article Last Updated: Mar 27, 2007}

    Type A Lactic Acidosis : Clinical Evidence of Inadequate Tissue Oxygen Delivery

    Anaerobic muscular activity (eg sprinting, generalised convulsions)

    Tissue hypoperfusion (eg shock -septic, cardiogenic or hypovolaemic; hypotension; cardiac arrest; acute heart failure; regional hypoperfusion esp mesenteric ischaemia)

    Reduced tissue oxygen delivery or utilisation (eg hypoxaemia, carbon monoxide poisoning, severe anaemia)

    Type B Lactic Acidosis: No Clinical Evidence of Inadequate Tissue Oxygen Delivery

    type B1 : Associated with underlying diseases (eg ketoacidosis, leukaemia, lymphoma, AIDS)

    type B2: Assoc with drugs & toxins (eg phenformin {a biguinide, but NOT metformin***}, cyanide, beta-agonists {some blood presure medications}, methanol, nitroprusside infusion, ethanol intoxication in chronic alcoholics, anti-retroviral drugs)

    type B3: Assoc with inborn errors of metabolism (eg congenital forms of lactic acidosis with various enzyme defects eg pyruvate dehydrogenase deficiency)

    Note: This list does not include all causes of lactic acidosis.

    *** Phenformin, a hypoglycemic agent used for type 2 diabetes, was withdrawn from the U.S. market in 1977 due to a reported rate of lactic acidosis of 40 to 64 cases per 100,000 patient-years. Metformin has been implicated as a cause of lactic acidosis because it is a related biguanide. However, metformin, unlike phenformin, enhances glucose oxidation without subsequently affecting fasting lactate production in peripheral tissues. Metformin has been in use for more than 40 years worldwide and has the positive effects of weight reduction and stabilization in addition to reductions in diabetes-related morbidity and mortality as reported by the U.K. Prospective Diabetes Study in the Sept. 12, 1998, issue of The Lancet. However, the true incidence of metformin-associated lactic acidosis is not known. Case reports have included patients with pre-existing renal or hepatic failure, both of which are contraindications to metformin use, and patients with hypoxia or hypoperfusion, which predispose to lactic acidosis. To date, 330 cases of lactic acidosis have been reported in such diabetic patients, according to the spring 1992 issue of the Archives of Medical Research. In clinical practice, 54% to 73% of patients receiving metformin have at least one contraindication to treatment, researchers report in the June 1997 issue of Diabetes Care. For example, in one cross-sectional study, 19% of patients receiving metformin after hospital admission had renal insufficiency.
    {in this article, go down to the section “The Biguanide Dilemma” for specific info on metformin}


  • acampbell

    Hi Marcie,
    Thanks for sharing all of this. Lactic acidosis is certainly a possible side-effect of taking metformin, but the incidence isn’t well-known, and is likely fairly low, although it’s more likely to occur in critically ill patients. Anyone who takes metformin needs to be aware of possible signs and symptoms, and should they occur, to seek medical attention immediately.

  • shiney


    Metformin is the ticket. When I was originally diagnosed, my level was over 500 – I thought I was pregnant. Well, my doctor gave me the 500 metformin. It didn’t do anything, so he gave me glipizide with it – worked wonders to bring my level down. so i stopped the metformin and stayed on the glipizide. Well, my feet started swelling
    and i gained another 15 pounds – but my sugar was under perfect control. Perfect. So when i got my sugar level under control, i was tired of the extra water and weight; i went on metformin only -which doesn’t cause weight gain. It causes diahrea at first but your body will adjust after about 2 months of taking it. If my sugar level gets too high, i will take like a 1/4 tab of the glipizide, which pulls everything immediately back in control; but makes my feet swell for a couple of days. Can you imagine 1/4 glipizide does this – it must be really strong – after that, my sugar is back in control and I only use a 1/4 tablet when necessary. Hope this helps. Stay on the metformin and use the glipizide if needed for excessively high readings.

  • Clara Marie

    Am a 74 year young diabetic 2 since 2009. Began to lose control (I was down to 6.4 earlier–after last Xmas went up to 8) My Dr gave me metformin,couldn’t stand feeling sick all the time so stopped, then Dr suggested Byetta. I was afraid of feeling worse so did research on web–the Diabetic Forum helped. The successful users all seemed to me to be eating 6 meals instead of 3.
    Now I had been a faithful reader of your magazine since I began having diabetes, don’t recall ever reading anything (not even ads) about any injectable medicine other than insulin. Also bought your Answer Book and it did help. This is my 4th day on Byetta and am still amazed at the no’s on my meter -I’m averaging 114 over the last
    3 days!! Could you give any advice on how to avoid
    the nausea all the users seem to have experienced?
    I have managed to stick to 3 smmaler meals + 3 fruit or cheese snacks. Thanks CMTardiff

  • acampbell

    Hi Clara Marie,

    So glad to hear that Byetta is doing its job for you! One of the most common side effects with this injectable medicine is nausea. However, the nausea is usually temporary and tends to go away. Since you’ve only been on Byetta for 4 days, try to hang in there and hopefully it will pass. If the nausea is too troublesome for you, you can try injecting it about 30 minutes (instead of 60 minutes) before your meal. Other tips include eating a little bit of fresh ginger root (available in your supermarket)or drinking some herbal peppermint tea (common anti-nausea remedies). If the nausea worsens, or if you develop vomiting or abdominal pain, call your physician right away.

  • donna

    I just saw an endocrinologist who decided I have metabolic syndrome and ordered a blood test to determine if I was a candidate for Metformin. After reading several posting on this site I have decided there is no way in heck I am going to take this drug. I have enough problems without adding anemia to them. I’ve been on the diabetic diet for hypoglycemia most of my adult life and about five years ago gained 30 lbs in less than 6 months. I’ve just recently discovered that the cause of this weight gain is probably a medicine I’ve been taking for approxamately the same span of time. I will discontinue this medicine gradually rather than introduce another problem causing medicine. Thanks to all of you who posted your experiences.

  • bharat

    Hi,, happy to have good information of metformin.
    My only question is If Extended release version of metformin is equally good as regular metformin, why to use frequently regular metformin?
    I am on metformin with lantus insulin, since many years
    Using plain insulin or metformin , will this is ok? or plain insulin is not needed at all if i use 500mg metformin twice a day. I am 60 yrs old and having familial diabetes type 2.
    Bharat Patel

  • acampbell

    Hi bharat,

    You ask a good question. The extended-release version of metformin came out after the regular version, and initially was intended to be given once a day. The extended-release version works longer in the body and also may be less likely to cause side effects, such as stomach upset and diarrhea. The decision to use one or the other is really up to the patient and the provider. Metformin can be used with insulin. Sometimes insulin is needed, especially at bedtime, to help control blood glucose levels overnight. The best way to see if you need to continue insulin is to check your blood glucose levels and bring your readings in to your doctor; another way to tell is your A1C level — if it’s not at your goal (usually less than 7%) your doctor will likely want you to continue taking insulin.

  • Bidarshi Barua

    Ihave been taking Metformin 1000 mg one in the morning and one in the evening with one Glyburide 6 mg. But some time not as effective as i need for. I used to take Glucovance befor Metformin and I am trying to recall that it was better than metformin itself. Another thing is Brand works better than Generic. But my insurance doesn’t pay for Brand.
    So, please either advise me for better Drug or advise me how do I get the Brand.


  • acampbell

    Hi Bidarshi,

    It’s possible that the Glucovance worked better for you than metformin and glyburide taken separately. However, might it be possible that your diet has changed (eating more carbohydrate, eating at different times) or your physical activity? It could be that you need a higher dose of glyburide, for example. Sometimes brand name medicines do work better than generics, but not always. This is really something you should talk to your doctor about. It would be helpful for you to show him your glucose readings for a week or so, along with your food intake, to help him make a decision about what medicine would be best for you.

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  • Auwal Ahmed

    Iam 50 years old, i was diagonised in 1996,and found that iam a diabetes patient. Since then i,ve been on Glucophage 500mg three times a day and also Dionil Tablet twice a day.

    The combination did good work for me for years, but now my sugar level is in high level.Most of the time i do fasting suger test it rises up to 360 or 20, and random reaches 585 or 33.

    i,try to control my diet but still level of the sugar fluctuate.

    I would like to have your advice please.

  • acampbell

    Hi Auwal,

    It sounds like you need a change in your diabetes medicines. Diabetes can change over time, even when you’re being careful with your diet and physical activity. Given that your blood glucose levels are quite high, I’d suggest you call your physician right away and let him know of your recent glucose values. Blood glucose levels that are continually this high are a cause for concern.

  • Richard

    For those with the runny poop and sickness there is Metformin XL which is made specificlly to pevent those side effects, and yes it does.

  • Richard

    Metforin XR, sorry

  • lindaf

    my husband was just diagnosed w/type II diabetes and he is currently taking medicine for restless leg syndrome (RLS) and he has high blood pressure.
    He takes Ropinirole Hcl 1 mg 2X a day.
    Could the metformin and the ropinirole
    cause any side effects. He ‘s only been on the metformin about 1 week but he’s having a lot more problems with the RLS?

    Also does Metformin and BP medication (Atenolol 50 mg 1 2X a day) have any side effects or contraindications?

    thank you

  • acampbell

    Hi lindaf,

    To the best of my knowledge, I don’t believe metformin is known to interact with Ropinirole or atenolol. However, everyone is different and people react to medicines differently, as well. You can ask your pharmacist about drug interactions, and if you think your husband’s RLS has gotten worse, I’d suggestion you call his physician.

  • DeniseG

    I just started taking metformin 500 mg once a day. my blood sugar levels are between 120 and 140 no matter what I eat and my A1C was elevated but not greatly when the doctor started me on this med about a month ago.My blood sugar levels have stayed the same since I started taking this drug, they have not gone down at all. I feel sick every day nauseous, shakey,my arms feel weak and sometimes my heart feel like its racing or irregular,I also feel like something is gnawing away at my stomach which feels like hunger but I don’t think it is. I have IBS which does not seem any worse. I haven’t lost any weight in fact I feel more bloated. My script said to take in the morning with food. I have to eat half my breakfast and then take it and then eat the rest and sometimes even doing that doesn’t help.I have never been able to eat much in the moring and am having a problem figuring out what to eat. I have very busy stressful job and can’t usually stop to eat every few hours. I saw that some people take it at night do you think that might help and why does mine say to take in the morning? I’m going on vacation soon and don’t want to be sick the whole time.

    • PJ Bear

      Are you still having these issues Denise? Send me a private message if you still are and I’ll try to help you.

  • acampbell

    Hi DeniseG,

    Since you just started taking metformin, your symptoms are likely side effects. It’s common to have gastrointestinal symptoms when first taking this drug; they usually subside, however. Most people start taking metformin in the morning, and then if the dose is increased, they may take it in the evening, as well. There is an extended-release version of metformin that is taken in the evening. One reason that you’re likely taking your dose in the morning is that it works during the day to decrease insulin resistance (which can occur after eating meals, for example). However, you might ask your doctor if you can try it at night time, instead. I don’t know if that will help your symptoms, but it may be worth a try. Also, you should tell your doctor about your symptoms, anyway. Some people just don’t tolerate metformin, so there may be another choice for you.

  • jim snell

    If you have leaky liver and nasty dawn effect ( 238) and strange liver dumps to 278/311, metformin is a miracle drug in big way.

    Timing of ingestion and dawn effect blocking has been verified using extensive data from CGMS.

    My timing is 500 mg dose taken 1 hour before each main meal and one at 10:00 pm and 12:00am midnight.

    The late night doses shut off dawn effect from midnight thru 5:30 am. 122 bg at midnight and 122 when I wake up at 5:30 am.

    The one hour before meals was obtained watching my digestion times and noting that usually gut would end and BG fall 2 hours after ingestion. If disturbances occur ib the falling BG whereby it tries to go back up, my liver would decide to hammer me up to 278/311. If metformin on duty up to strength in blood, liver does not do phony sympathetic dump – ie actual BG was in the 150 to 210 range. Why the liver dumps – I have no idea.

    Anyways with above approach, my BG is great and no sneaky liver dumps in weeks.

    Oh yes, metformin ER not good – especially teva brand. Taking one large dose rather than timed doses as noted is dumb and waste of drugs.

    You must not try this unless you have reviewed with your Doctor and you have CGMS to monitor live. Also you need to know all the timing on your own body – drug ingestion time, up to strength and decay.

  • MG Ramirez

    I am currently on metformin and have been on it for 1 year now. My question is I donated a kidney to my father in 1973. In 2002 I was diagnosed with type 2 diabetes. My sugar level is my problem and the lowest I have had it is 175. I have just started having Lactose intolerance symptoms, should I be concerned?

  • acampbell

    Hi MG,

    Metformin is a very effective medicine for treating Type 2 diabetes. As with all medicines, though, there are possible side effects of metformin that include stomach upset, gas, nausea, and diarrhea. Generally, these symptoms go away a short while after starting on metformin. Lactose intolerance can cause symptoms very similar to the side effects of metformin. I’d advise you to let your doctor know about your symptoms so that he or she can better determine the cause of them. You should also review your diabetes treatment plan with your doctor, given that your blood glucose levels are running high. You may need a larger dose and/or another type of diabetes medicine to bring your blood glucose levels into a safe range.

  • Constance Burnett

    I am experiencing a number of side effects since I have been taken metformin. The most annoying is my abdomen has been swelling. I am not gaining weight but my stomach and my chest have enlarged immensely and I dont know what to do.

  • acampbell

    Hi Constance,

    Metformin is a very safe and effective medicine for helping to treat Type 2 diabetes. However, it’s quite common for a person to experience side effects when first starting this drug. Diarrhea, nausea, vomiting, gas, and bloating are a few of the most common symptoms. The symptoms typically go away soon after starting metformin, but I’d advise you to call your doctor. You may need to cut back on your dose, or, if your bloating is very bothersome, stop the metformin altogether.

  • ABuckman

    I have recently began taking GLucophage 500mg BID. I had tried it years ago and refused to take it because of the side effects i endured. I noticed that sometimes I take it and am not sick at all but most times I get sick about 2 hours after taking it and the stomach pains last for housrs. Just when it is going away it is time for my net dose. My doc suggested i take it with my two biggest meals of the day. Today i told him it doesn’t seem to help with the side effects. He suggested that I take it immediately AFTER I eat instead of before since my stomach is already coated with food and churning it up. We shall see how this works out. I have only been following up on the diabetes for a month now and my levels are still averaging 180 for fasting! its all about my diet! its so hard to change 36years of a carb loving diet!!
    He promised that my body will get used to the drug and also that when my sugars are under control it will be even better. Also my cravnigs will become easier to manage. Right now i feel like I could strangle a stranger to steal his cupcake! does anyone have any tips for getting thru those cravings and those of you who dealt with the side effects of glucophage and now are ok with it, did you notice a different depending on the food you ate with it and how long until your side effects lessened???

  • Joann

    Im currently diagnose with PCOS and was prescribe metformin 250mg oral daily. Is the dosage sufficient for me to even loose weight..? and when is the best time to take it.?

  • acampbell

    Hi Joann,

    As you’re likely aware, PCOS (polycystic ovary syndrome) is associated with high insulin levels and insulin resistance. Metformin is often given to women with PCOS as a way to help reduce the insulin resistance. Metformin can also help with weight loss which can also help with insulin resistance and irregular menstrual cycles, as well as helping to promote ovulation. The usual dose of metformin for PCOS treatment ranges from 1000 to 2000 mg per day. However, because of its possible side effects, it’s usually recommended to start off with a low dose and gradually increase to the maximum dose. Ask your provider what your “final” dose of metformin should be and what he suggests for a dosing schedule.

  • lisa

    My fathers dr. Just prescribed him 1000 mg of metformin plus glucovance 2.5-500 is it safe to be taking that together I am worried it may be too much metformin.

    • Scott Maxwell

      Yes. They attack diabetes in different ways. The glucovance is a faster acting med and the metformin is a long acting.

      I take 4 mg of Ameryl and 1000 metformin in morning and 1000 metformin at night meal. So using both is not that uncommon.

  • acampbell

    Hi lisa,

    The maximum dose of metformin is 2500 mg per day. From what you wrote, it appears that your father is getting 1500 mg (total) of metformin, plus 2.5 mg of glyburide, so that seems safe. However, if your father is taking a higher dose of either the metformin and/or the Glucovance, then it would certainly be possible to get too much metformin. If you or your father have any questions or concerns about his medicines, please speak with his doctor to be on the safe side.

  • Bruce Davis

    Hello everyone my name is Bruce. At the end of 2013 I was diagnosed with type 2 diabetes. I was hospitalized immediately because my blood sugar levels were above 500. I was 46 years old at the time and thankfully up until that point the sickest I have been in my life was a minor stomach virus. I had never taken a prescription drug . I hated the fact I I allowed myself to to reach this point. My diet, stress levels, and overall weight management was out of control. There are some disciplines we own that I am not hearing about on this blog, Everyone is talking about the drug but I have not read a single update about what you are doing to change your personal habits. Are you exercising? Are you eating better? What have you changed other than pick up medicine?

  • Jay Olivo

    My mom is taking this medication but she hates it tho. Takes all her energy plus gives her headaches . What can she do? Whats another medication she can take besides this one???

    • PJ Bear

      The reason Metformin robs the body of energy is it depletes Vitamin B12. Tell your mom to either get regular B12 shots or find some enteric coated B12 pills. They must be enteric coated to protect the Vit B12 from stomach acids. Once she starts doing this she will notice an improvement in her energy levels..but she must be consistent about taking the B12. Metformin is the safest drug for diabetes. It has been around for decades..unlike these new drugs that can cause all kinds of problems. If it is controlling her blood sugar and the lack of energy is the only issue try the B12.

      • Isabella Buchanan

        B12 skin patches are better for a lot of people, I’ve heard.

  • Patti

    I was diagnosed with type 2 diabetes one year ago. Doctor started me on the Metformin ER 1000mg once per day. I took it with my evening meal. It lowered my blood sugar immediately and worked great for about 9 months, but then I could tell it wasn’t working as well. I was getting sleepy during the day (especially following a meal), and I had those evening food cravings again which were under control for awhile. Sure enough, I just got my test results and I moved from 6.3 A1C up to 6.5 so I am going the wrong direction. Saw my doctor yesterday & she wants to increase my Metform ER to 2000mg per day and she said I would take it all at the same time with the evening meal. I have not gone yet to the pharmacy to pick up the meds as I am afraid to take that much at one time. So I have a couple of questions. First, is it better to take 1000 mg of Metform ER in the morning and then 1000 in the evening or all 2000mg at one time? Also, the ER version is very expensive…so I’m wondering if I might suggest that we MIX the two??? Is it possible to take Metformin ER 1000mg in the evening and then during the daytime take the regular Metformin? Just wondering if these two forms of Metformin can be mixed???

    • PJ Bear

      I take 1000mg of Metformin ER twice a day. It works well for me..but I have noticed that if I don’t eat a low carb diet it only does so much. You really have to go low carb to reap the full benefits. As a matter of fact..if you do go low carb you will usually be able to cut your Metformin use by 50% in about a month..and some people are able to stop it altogether..but you MUST inform your doctor of what you are doing so they can monitor you. Carbs seem to be the biggest issue for type 2 diabetics..which is a shame because I love them. As for the price of Metformin ER..send me a private message and I can give you some advice that saved me a lot of money purchasing it.

      • Scott Maxwell

        You have to use protein carbs rather than sugar carbs. Also keep away from foods that convert to starches. These will affect your sugar levels also.

    • Cherice

      @Patti, I was diagnosed only 6 months ago, and the metformin has been a battle for me as well… I started of great… one metformin 500mg. A1c was 8.9, restested a month and half almost 2 months later I got it down to 7.4, but I was also swimming, walking, and working out, mostly swimming… just how ever many laps I could do in one hour. Then Oct, Nov, Dec. came, and I got a cold, and wasn’t working out and the average blood sugar according to Kaiser IQ verio meter was 167, so the doctor increase metformin to 1000mg… (I wished they didn’t do that), but then my number were completely out of control… in the beginning of January, it was like I started over completely… Blood Sugar on 3 metformin 1500mg ER, I had to adjust eating and everything… I do not use the Kaiser meter I don’t think it works, it reads 50-60 and some time 75 points higher than normal non usb meters… and the non usb meter matches the doctors office, so we are going with the new meter I purchased that matches closer to doctor’s office readings… and I walk 30min at lunch and 30-45 after or before dinner… My numbers are falling back in line like they did the first two months I was diagnosed, but I got bad results when I was taking it 3 at night… because my sugar was high all throughout the day… So I started taking One with breakfast, and two and night. and then number started to adjust. No I take one with every meal, and blood sugars are in a normal range… example morning reading 99, check blood before lunch 147, walked 30 blood sugar 77 (only had one metformin so far). Ate lunch with metformin, and I will check it before dinner, and rollerskating to see where its at… and I am praying by Feb 28, then I test again, I will able to go back down to 1 or 2 metformin, until I can completely come off them with diet and exercise… It’s a struggle, but hang in there… before you mix the meds, if you are not walking try that first, or forgive me I don’t want to assume anything… but if you are not exercise… it could help, so that way you don’t have to increase medication at all… just a thought. Hope this helps

  • Cherice

    @Patti, I was diagnosed only 6 months ago, and the metformin has been a battle for me as well… I started of great… one metformin 500mg. A1c was 8.9, restested a month and half almost 2 months later I got it down to 7.4, but I was also swimming, walking, and working out, mostly swimming… just how ever many laps I could do in one hour. Then Oct, Nov, Dec. came, and I got a cold, and wasn’t working out and the average blood sugar according to Kaiser IQ verio meter was 167, so the doctor increase metformin to 1000mg… (I wished they didn’t do that), but then my number were completely out of control… in the beginning of January, it was like I started over completely… Blood Sugar on 3 metformin 1500mg ER, I had to adjust eating and everything… I do not use the Kaiser meter I don’t think it works, it reads 50-60 and some time 75 points higher than normal non usb meters… and the non usb meter matches the doctors office, so we are going with the new meter I purchased that matches closer to doctor’s office readings… and I walk 30min at lunch and 30-45 after or before dinner… My numbers are falling back in line like they did the first two months I was diagnosed, but I got bad results when I was taking it 3 at night… because my sugar was high all throughout the day… So I started taking One with breakfast, and two and night. and then number started to adjust. No I take one with every meal, and blood sugars are in a normal range… example morning reading 99, check blood before lunch 147, walked 30 blood sugar 77 (only had one metformin so far). Ate lunch with metformin, and I will check it before dinner, and rollerskating to see where its at… and I am praying by Feb 28, then I test again, I will able to go back down to 1 or 2 metformin, until I can completely come off them with diet and exercise… It’s a struggle, but hang in there… before you mix the meds, if you are not walking try that first, or forgive me I don’t want to assume anything… but if you are not exercise… it could help, so that way you don’t have to increase medication at all… just a thought.

    • Scott Maxwell

      My doctor wants me to be below 7.0 A1C. The exercise is one of the best ways to help and take your medicine on a regular basis. I had a spinal infection that make exercise hard so I have to watch my food intake well to keep under control.

  • xtaski

    My Mom is 87 and has had surgery for pancreatic cancer (whipple procedure). About 5 years ago she began taking metformin 500 mg x 2 and after 2+ years I posted to a diabetes board and was told about metformin ER which she now takes (500mg x 2 in AM). Her fasting blood sugars are good (85, 100, 94, etc) but it is after breakfast ones that are not so good (159, 169, 174). Her breakfast usually consists of special K high protein cereal, few walnuts or almonds (sometimes both), few berries and 1/2 lactaid on the cereal. Her doc is insistent she take metformin er in the AM but all the articles I have read say to use in PM. Would this help her after breakfast numbers? BTW she is 100 pounds.

    • acampbell

      Hi xtaski,
      Has your mother’s doctor given her a post-meal blood sugar target? For many people with diabetes, the 2-hour post-meal blood sugar goal is less than 180. Given that, your mother’s after-breakfast readings really aren’t that high. Her breakfast seems reasonable, too. From my understanding of metformin ER, the main point is to be consistent about taking it at the same time each day. Some people do take it in the evening and find that doing so helps their morning glucose readings. You might also ask your mother’s pharmacist, too.

    • Scott Maxwell

      My fasting level is not to be below 90 and my after meals we try to maintain 187. So you are close. My weight is 210 lbs. But weight is not the major issue, it is the amount of insulin that you pancreas produces. Eating food with lots of starch can also convert to sugars in the blood stream.

      So it is important to keep you medicines at a regular time and to monitor what you eat. If you have food that drives you too high, you may want to cut back on them.

  • acampbell

    Hi Linda,
    Based on my understanding of this medicine, it should be taken once a day, usually in the evening. You should double check with your pharmacist and/or cardiologist about how your prescription was written.

  • Sharon Minton

    I have type 2 diabetes.During the Easter weekend,I was hospitalized for pneumonia,a blood infection,and my blood sugars had gone down to 30.After I got out a week later,the doctor at the hospital had put me on Lantus long-acting insulin-even though my A1C at the hospital was 5.5 I couldn’t understand why they did that-but a month later,I was taken off the shot and put on metformin hcl er-750 mg. once a day with the evening meal.Why is it that I have to take it in the evening?Does it take awhile to get into my system? It almost sounds like the long-acting insulin I was on,that took 8 hours to get into my system.

    • Scott Maxwell

      Your blood sugar level at 30 would be a real problem. They usually want it no less than 80. If you get below this you may feel different and at the lower levels like you were, you could become unconscious and even die.

      I was an EMT for 30 years and dealt with many cases of both Hyper and Hypo glycaemia. We often had to give D50 through an IV to bring people up from low levels. When they received the medication, they usually came around quickly.

      D50 is like pushing molasses through a needle.

  • carmel sorrento

    do i take my medformin in the morning or evening or can i split the meds some in the morning and some in the evening?

    • acampbell

      Hi carmel,

      Great question. Your doctor has hopefully told you when to take your metformin. Some people take it twice a day, morning and before dinner, for example. The extended-release version of metformin is taken once a day. If you’re not sure when to take it, check back with your doctor or ask your pharmacist. Also, double check your prescription, as directions may be written on that, too.

  • Scott Maxwell

    I am taking 2000 mg a day and also have glimepiride 4mg in morning. I have no issue with bowels and such and have had not medication incidents with hypo reactions.

    SO your dose if not uncommon. The doctor gave me the 1000 mg twice a day rather than 2 x500 morning and night meal.

  • Wayne Wastier

    I am thinking about changing my current med, Glucovance generic 5/500 4 times a day to Januvia since my HMO no longer covers Glucovance generic or retail, but it does cover Januvia. What would be the equivalent dosage of Januvia?

  • Rick Holzworth

    Why should this medication be taken at night with dinner?

    • acampbell

      Hi Rick,

      Metformin is generally taken twice a day — in the morning and in the evening. It’s recommended to take metformin with a meal so that it can be better absorbed.