Insulin Types

Insulin can be an important part of an overall diabetes treatment plan, including diet, exercise, and oral diabetes medications. Insulin may be taken alone, with other insulin, or with oral diabetes medications. Different types of insulin are made for different needs, schedules and situations. The two main insulin types are basal insulin and mealtime insulin.

Basal insulin

Basal insulin describes the slow, steady release of insulin. This kind of insulin is needed to supply energy to cells when no food is being digested. Basal insulin includes long-acting and intermediate-acting insulin:

• Long-acting insulin begins to work anywhere from 1 to 10 hours after injection. It can work for up to 24 hours.
• Intermediate-acting insulin begins to work 2 to 4 hours after injection. It peaks 4 to 12 hours later, and works for 12 to 18 hours.

Mealtime insulin

Depending on the product, mealtime insulin might be taken either before, during or after a meal. It works like the insulin your body would normally make when you eat. This kind of insulin controls blood sugar levels during meals. Mealtime insulin includes regular (short-acting) and rapid-acting:

• Regular or Short-acting insulin begins to work in about 30 minutes. It peaks 2 to 3 hours after injection, and works between 3 and 6 hours.
• Rapid-acting insulin begins to work about 15 minutes after injection. It peaks in about half an hour, and works for 2 to 4 hours.

Sometimes rapid and intermediate insulin are provided together in predetermined amounts called premix insulin.

Insulin does not always need to be refrigerated. Many people store insulin they are currently using at room temperature because they find it more comfortable to inject. Refrigerated, unopened insulin is good until the expiration date printed on the product. Always read the instructions that come with your insulin.