Insulin is a powerful hormone produced by beta cells in the pancreas that helps cells turn blood glucose into energy. When the body either doesn’t make insulin or doesn’t respond well to it, the complications of diabetes arise.
Everyone with type 1 and some people with type 2 diabetes need to use insulin to manage their diabetes. People with type 1 diabetes have to take insulin because their pancreas no longer produces it. Some people with type 2 diabetes need to take insulin, as they have insulin resistance, wherein their sensitivity to insulin is impaired.
The most common strength of insulin is U-100, or 100 units of insulin per milliliter of fluid. When traveling outside the U.S., be sure to match your insulin strength with the correct syringe size.
Stages of insulin
There are different stages of insulin’s efficacy:
- Onset is when the insulin first starts to work.
- Peak is when your insulin is working the hardest.
- Duration is how long the insulin works in your body.
Each type of insulin varies in onset, peak, and duration.
Types of insulin
There are different types of insulin:
- Rapid-acting insulin. This type begins working 15 minutes after injection, peaks in around 1 hour, and can last from 2 to four 4 hours. Rapid-acting insulin is used before a meal to regulate blood sugar. (Examples: Apidra, Humalog, NovoLog)
- Regular insulin (short-acting insulin) begins working 30 minutes after injection, peaks 2 to 3 hours after injection, and lasts for 3 to 6 hours. (Examples: Humulin R, Novolin R)
- Immediate-acting insulin reaches the bloodstream 2 to 4 hours after injection, peaks in 4 to 12 hours, and lasts for 12 to 18 hours. (Examples: Humulin N, Novolin N)
- Long-acting insulin takes several hours to reach the bloodstream and takes effect evenly over a 24-hour period. (Examples: Levemir, Lantus)
Some people also need to use premixed insulin, if they need a mix of two different types. Also a relatively new arrival is inhaled insulin (Afrezza). Inhaled insulin is rapid-acting and usually taken at the beginning of a meal. Inhaled insulin is only for adults. Afrezza is used in conjunction with injectable long-acting insulin. Inhaled insulin begins working in 12 to 15 minutes, peaks in 30 minutes, and lasts 180 minutes.
Ways to take insulin
There are a few different ways to take insulin.
- Needle and syringe. This is the most common way to take insulin. It works best to inject it into your belly, but rotate spots throughout the week so the skin doesn’t get too tough. Other possible injection sites are the thigh, buttocks, or upper arm. Your doctor will recommend how many times a day you need to take insulin.
- Insulin pen. Though these are more costly that a needle and syringe, many find them more comfortable and convenient to use. Insulin pens are either disposable or have an insulin cartridge that you insert.
- Insulin pump. An insulin pump connects to your skin and can give you doses of insulin throughout the day. If using a pump, it’s important to also stay on top of your insulin, carbohydrate intake, and blood glucose, checking your blood glucose at least 4 times a day. You’ll need to adjust your insulin dose based on your blood glucose readings, your carb intake, and any physical activity you do.
How to store insulin
Insulin should be refrigerated until you use it. Once opened, it should last 2 weeks to a month depending on the type. Check your prescription’s insert for specifics. Here are a few tips for storing insulin:
- Don’t store insulin near extreme heat or cold.
- Never store in a freezer, in direct sunlight, or in a glove compartment.
- Always check the expiration date and don’t use insulin beyond its expiration date.
- Look at the insulin closely before you use it to make sure it looks okay.
Insulin reactions
Taking insulin can lead to hypoglycemia, or very low blood sugar. Different insulin reactions can occur if you get a lot of physical activity and don’t eat enough. These include:
- Fatigue
- Trouble speaking
- Sweating
- Confusion
- Losing consciousness
- Seizures
- Muscle twitching
- Pale skin
To alleviate an insulin reaction, carry snacks with you that will boost your blood sugar, like a half cup of fruit juice or two tablespoons of raisins.
