6 Do’s and Don’ts of Insulin Injection

If you’ve been newly prescribed insulin, you may be feeling overwhelmed. Where do you inject it? When? How often? How is it stored? Your healthcare provider will have plenty of answers for you, but here are some easy-to-remember tips.

Different types of insulin work at different speeds.

• Rapid-acting starts working about 15 minutes after injection and continues for 2 to 4 hours.
• Short-acting reaches the bloodstream in 30 minutes and wears off after 3 to 6 hours.
• It takes about 2 to 4 hours for intermediate-acting insulin to start working, and it continues to work for 12 to 18 hours.
• Finally, long-acting insulin takes several hours to reach the bloodstream and remains effective for about 24 hours.

It’s true you shouldn’t vary which general body part you inject your insulin, but you also shouldn’t inject your insulin in the same specific spot every time. Doing so can create lumps and fatty deposits that can reduce the effectiveness of the insulin. It may be less painful to inject into these lumps, but it could change how well your insulin works. Stay away from bruises, scars, and your belly button.

Insulin needs to be injected into fat. Be sure to relax the area around the injection site. If you’re tense, the nerves will be more sensitive to pain. Use a short, thin needle to avoid piercing the muscle and causing more pain, and stick to room-temperature insulin, if possible.

When storing insulin, make sure to check the label and follow all instructions. Unopened insulin will last until the expiration date, and you can keep it in the refrigerator. Opened insulin can be kept at room temperature for about 30 days. In fact, room temperature insulin may be less painful when injected. Do not freeze insulin, and don’t store it anywhere where temperatures reach more than 86 °F.

Some insulin may look cloudy or opaque in the bottle. That means it’s a suspension—a liquid with particles in it. But if it’s supposed to be a clear solution and it looks cloudy, throw it away. Insulin suspensions need to be rolled around in the palm of the hand in order to mix. Don’t shake vigorously or the insulin can clump together. Throw away any clumpy insulin.

It’s important to be consistent with the time at which you inject your insulin and when you eat. Know how long it takes for your insulin to hit your bloodstream, and time your meals so that your blood sugar rises as your insulin takes effect. Injecting insulin and eating around the same times every day takes some of the guesswork out of managing your condition.