What is short-acting insulin?

Sometimes referred to as regular insulin or neutral insulin, short-acting insulin is meant to be taken before meals to cover your insulin needs for a rise in blood sugar from eating.

When does short-acting insulin peak and how long is it active?

Short-acting insulin will usually reach the bloodstream (onset) within 30 minutes after injection, will peak after two to three hours, and remains effective for approximately three to six hours.

When should I take short-acting insulin?

Short-acting insulin, similar to rapid-acting insulin, is meant to cover your insulin needs during meals, but rather than injecting it immediately before eating, short-acting insulin is taken 30 minutes to an hour before starting your meal.

Which products should I look for?

If your doctor prescribes short-acting insulin, he or she will give you regular R insulin under the brand names Humulin R or Novolin R.

Anything else I should know?

Some people prefer short-acting insulin because you don’t have to take it at each meal, only at breakfast and dinner because it lasts longer than rapid-acting insulin. Short-acting insulin is generally prescribed alongside a longer-acting insulin as well.

Learn more about insulin:

Everything You Need to Know About Rapid-Acting Insulin
Everything You Need to Know About Intermediate-Acting Insulin
Everything You Need to Know About Long-Acting Insulin