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Insulin degludec

Brand names: Tresiba, Xultophy (with liraglutide)

Insulin degludec is an ultra-long-acting insulin that keeps blood sugar steady for more than a day.

Brand namesTresiba, Xultophy (with liraglutide)
Type of medicineLong-acting insulin
Prescription?Prescription
ImportantThis page is general information, not a prescription. Don't start, stop, or change a medicine without talking to your provider or pharmacist.

Overview

Because it lasts so long, the time of day you take it can be flexible.

What it's used for

  • Type 1 diabetes (with mealtime insulin)
  • Type 2 diabetes
  • Children 1 year and older

How to take it

  • Inject once a day, ideally at about the same time; doses should be at least 8 hours apart.
  • Rotate injection spots.
  • Never share pens.

Your dose depends on your health and other medicines. Always follow your prescription label, and ask your pharmacist if anything is unclear.

Side effects

Common side effects

  • Low blood sugar
  • Weight gain
  • Redness or lumps where you inject
Call 911Severe low blood sugar: confusion, seizure, or passing out. Use glucagon if you have it, then call 911.
Call your provider todayFrequent low blood sugar or readings that stay high

Warnings

  • Never mix it with other insulins.
  • Know the signs of low blood sugar and keep fast sugar with you.

Other medicines, foods, and alcohol

  • Other diabetes medicines add to low blood sugar risk.
  • Beta blockers can hide signs of low blood sugar.

Tell your provider and pharmacist about every medicine, vitamin, and supplement you take.

Pregnancy and breastfeeding

Talk with your provider about insulin choices in pregnancy.

Missed doses, overdose, and storage

If you miss a dose

Take it as soon as you remember, making sure at least 8 hours have passed since the last dose. Then go back to your usual time.

If someone takes too much

Call Poison Control at 1-800-222-1222 or get help online at poison.org. Call 911 if the person collapses, has a seizure, has trouble breathing, or can't be woken.

Storing it

Keep unopened pens and vials in the refrigerator (don't freeze). Once opened, follow the label for how long it lasts at room temperature.

Conditions it's used for

Sources

Last updated 2026-11-13.