Medication Information Leaflet

What is this medication for?

Mepolizumab is an antibody, selective for interleukin-5a, which plays an important role in the inflammation process. It is used to treat severe asthma by helping to reduce inflammation in the airways.  

How should I take/use this medication?

  • Use exactly as how your healthcare professional has told you. 
  • Do not stop your medication without checking with your healthcare professional.

Mepolizumab comes in pre-filled syringe, pre-filled pen and powder for solution for injection. Please refer to the individual product inserts to administer the medication.

  • Check the expiry date of the injection, do not use if it has passed the date.
  • In general, allow the injection to sit at room temperature for 30 minutes after removing it from the fridge before administration. Do not shake or share or re-use the injection. 
  • The injection should be clear to pale yellow in colour. Do not use it if you notice any discolouration, cloudiness or particles. Small air bubbles may be seen and it is acceptable. 
  • You can inject under the skin into the fatty tissue either into the upper arm, thigh or abdomen. 

What should I do if I forget to take/use this medication?

  • If you forget to use a dose, do it as soon as you remember. Then use your next dose at the scheduled interval (for example, 4 weeks or 8 weeks from the administered date). Do not take two doses to make up for the missed dose.

What precautions should I take?

Inform your healthcare professional if: 

  • You are allergic to this medication or any of the other ingredients of this medication
  • You are pregnant, planning to become pregnant, or breastfeeding 
  • You are taking any other medications, including supplements, traditional medications and herbal remedies 

What are some common side-effects of this medication?

The side effects for Mepolizumab are usually mild and generally well tolerated. They include the following: 

  • Burning sensation, redness, pain or itching at the injection site 
  • Headache 
  • Mouth or throat pain
  • Back pain
  • Tiredness

These symptoms may happen but should get better over time. Check with your doctor if any of these symptoms are serious or do not go away.

What are some rare but serious side-effects that I need to seek medical advice immediately?

The symptoms of a drug allergy include one or more of the following: 

  • Swollen face/eyes/lips/tongue
  • Difficulty in breathing
  • Itchy skin rashes over your whole body

If you experience any of these symptoms, you should stop your medication and see your healthcare professional immediately.

What food or medication should I avoid when I take this medication?


How should I store this medication?

Store in refrigerator (2-8 °C). Do not freeze. Do not expose to heat. Store the injection in the original packaging to keep away from light. Keep this medication away from children. 

How should I throw away this medication safely?

If used at home, you may throw away the injection along with the used needle in a puncture proof container, such as a metal tin or thick plastic bottle with cap or cover (for example, detergent bottles). You can also buy a container specially designed to throw sharp items, known as a sharps box, at pharmacies. This is to prevent any injuries due to needles. Pack the container into a black trash bag and seal it tightly before throwing it into the rubbish chute or bin.

If used at the hospital, your healthcare provider will dispose of the injection and needle in an appropriate container. 


Please take note that the above is not a complete list of all possible side effects. If you have any concerns about your medication or if you have other side effects that you think are caused by this medication, please consult your doctor or pharmacist.

If you take more than the recommended dose, please seek medical advice immediately. The information provided on this page does not replace information from your healthcare professional. Please consult your healthcare professional for more information.

This article is jointly developed by members of the National Medication Information workgroup. The workgroup consists of cluster partners (National Healthcare Group, National University Health System and SingHealth), community pharmacies (Guardian, Unity and Watsons) and Pharmaceutical Society of Singapore. The content does not reflect drug availability and supply information in pharmacies and healthcare institutions. You are advised to check with the respective institutions for such information.

Last updated on Apr 2023 


Back to Top