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Mepolizumab

Brand names: Nucala

Mepolizumab is a monthly shot that lowers attacks in severe eosinophilic asthma and treats nasal polyps and some rare conditions.

Brand namesNucala
Type of medicineBiologic (IL-5 blocker)
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

It lowers eosinophils, the white cells that drive this type of asthma.

What it's used for

  • Severe eosinophilic asthma
  • Nasal polyps
  • EGPA and hypereosinophilic syndrome
  • COPD with high eosinophils

How to take it

  • Inject under the skin every 4 weeks.
  • Keep using your other asthma medicines.

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

  • Headache
  • Injection site reactions
  • Back pain
Call 911Swelling of the face, lips, or throat, hives, or trouble breathing
Call your provider todayShingles rash

Warnings

  • Don't stop steroid medicines suddenly when starting.

Other medicines, foods, and alcohol

  • Few interactions.

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

Pregnancy and breastfeeding

Talk with your provider.

Missed doses, overdose, and storage

If you miss a dose

Take it as soon as you remember, unless it's almost time for your next dose. Then skip the missed dose. Don't take two doses at once.

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

Store at room temperature, away from heat and moisture (not in the bathroom), and out of reach of children and pets.

Conditions it's used for

Sources

Last updated 2026-11-13.