Injection aids. Various types of injection aids can make injecting with a syringe easier in some situations. Injection aids that hide the syringe needle can be helpful for people with needle phobia. Those that guide or insert the needle into the skin or that insert the needle and inject the insulin can be useful for children who give their own injections, people who have difficulty seeing, or people who have unsteady hands, pain or numbness in their hands, or difficulty manipulating syringes for some other reason. Vial stabilizers and syringe magnifiers may be helpful in drawing up accurate doses of insulin. Brightly colored vial sleeves and caps can help with identifying different types of insulin if more than one type is used.
Before purchasing any kind of injection aid, make sure it is compatible with the type and brand of syringes you use.
Insulin pens look similar to oversized ink pens, making them a potentially convenient and discreet way of carrying insulin. To use an insulin pen, the pen cap is removed and a pen needle is attached. The pen is then “primed” by dialing in a very small dose (exactly how much depends on the particular pen) and expelling the insulin into the air. Priming is done to ensure that insulin is flowing through the pen properly and that there is no air in the cartridge or needle.
After priming is completed, the actual dose of insulin to be administered is dialed in using a dial or dose knob. The needle is inserted into the skin, and the dose is delivered by pressing on the dose knob until it is fully depressed. It is important to hold the pen in place and to continue pressing the dose knob while counting slowly to five before removing the needle from your skin to ensure that no insulin leaks out. Pen needles are intended for one use only and should be removed and discarded after an injection.
Insulin pens should never be stored with the needle still attached because doing so may allow insulin to leak out or air bubbles to form in the insulin cartridge. Between uses, the pen’s cap should be put on to protect the insulin cartridge. In-use pens or pen cartridges should not be stored in the refrigerator because of the possibility that condensation will form in the insulin container. (As soon as an insulin cartridge is placed in a pen, it is considered “in-use” and should no longer be stored in the refrigerator, even if the pen is not actually used for an injection for several days.)
Most pens hold 300 units (3 ml) of insulin and deliver doses in one-unit increments, with up to 60 to 80 units per dose. The NovoPen Junior and the HumaPen Luxura HD deliver insulin in half-unit increments. One of the biggest advantages of insulin pens is accurate dosing. Ease of use is another advantage of pens over syringes because they require less manual dexterity and coordination, and they may be easier to use for people with low vision.
Like syringes, pen needles also come in a variety of needle gauges and lengths. However, pen needles may be slightly thinner and in some cases shorter than syringe needles, so injections may be more comfortable.
Some pens are disposable, while others use replaceable cartridges of insulin that are inserted into the pen.
Prefilled pens. Prefilled, plastic, disposable insulin pens have a self-contained insulin cartridge. Several different types of insulin are sold in prefilled pens. Once you have used all of the insulin in the cartridge (or the insulin has reached its in-use expiration date), you dispose of the entire pen.
While most insulin pens look like writing pens, one exception is the InnoLet, a disposable device that looks more like a kitchen timer with a big round dial. The big dial with large, easy-to-read numbers makes the InnoLet easier to use for some people with visual difficulties or dexterity problems. In addition, the relatively large size of the device also may make it easier to hold securely against the skin while administering insulin doses, particularly for people with arthritis, tremors, or shaky hands. The InnoLet holds 300 units of insulin.