Montelukast is a commonly prescribed medicine in the UK, used for asthma. If you have just been prescribed montelukast, this page explains what it is, the brands and strengths it comes in, how to take it, and how to have it dispensed and delivered free on the NHS with PillSorted.
This content has been medically reviewed and approved by Zeinab Ardeshir (GPhC 2075730), Superintendent Pharmacist at PillSorted (GPhC-registered online pharmacy 9011258). Last reviewed: 14 July 2026.
What is montelukast?
Montelukast is a tablet that helps control asthma and allergy symptoms by reducing inflammation and narrowing in the airways. It is a preventer, not a reliever.
Brands and strengths
Montelukast is the name of the active ingredient. In the UK it is sold as generic montelukast and under brand names including Singulair and Amecas — all contain the same active ingredient and work the same way. Common strengths:
- Montelukast 4 mg tablets
- Montelukast 5 mg tablets
- Montelukast 10 mg tablets
- UK brands: Singulair and Amecas
What montelukast is used for
- Asthma (add-on preventer)
- Allergic rhinitis (hay fever)
How to take montelukast
Usually taken once a day in the evening. Keep taking it regularly even when you feel well — it works by preventing symptoms. Always follow your prescriber’s instructions (BNF).
Side effects
Common effects include headache and tummy ache. Tell your prescriber about mood or sleep changes, or vivid dreams. This is not a full list — see the patient information leaflet (BNF).
Montelukast: frequently asked questions
Yes. Singulair is the original brand name for montelukast; the generic is the same active ingredient.
No — it is a preventer taken daily, not a reliever. Keep using your reliever inhaler for symptoms.
Yes. If you have an NHS prescription for montelukast, you can nominate PillSorted as your NHS pharmacy and we will dispense and deliver it to your door for free.
Get your montelukast delivered free on the NHS
If you have an NHS prescription for montelukast, PillSorted dispenses and delivers it to your door — completely free. Nominate PillSorted as your NHS pharmacy once, and we take care of your repeat prescriptions from then on.
What you get
- Free delivery, every time — your medicine posted to your door, always free.
- Your whole family, one account — manage everyone’s prescriptions in one place.
- Real pharmacists, every prescription — every order checked by our UK pharmacist team.
How it works
- Choose PillSorted as your NHS pharmacy
- We collect your prescription from your GP
- Your medication is delivered free to your door
Sources: NICE; BNF — Montelukast.
This page is for general information only and is not a substitute for advice from your GP or pharmacist. Always take your medicine exactly as prescribed. For advice about your own health, consult a clinician.