Omeprazole
Also known as: Losec, Pyrocalm
What it's for
Omeprazole reduces the amount of acid your stomach makes. It treats heartburn, acid reflux, stomach ulcers, and helps protect your stomach if you take anti-inflammatory medicines.
Comes as: Capsules or tablets
How to take it
- Adults: Usually 20mg once a day, in the morning.
- Swallow the capsule whole with water. Do not chew or crush it.
- Take 30 minutes to 1 hour before food for best results.
- For heartburn, you may only need to take it for 2 to 4 weeks.
Doses here are typical. Always follow the instructions from your prescriber or on the packet — they come first.
Common side effects
- Headache
- Stomach pain, wind, or diarrhoea
- Feeling sick
The leaflet inside the packet lists all known side effects.
Important safety points
- Not usually suitable for long-term use unless advised by your doctor
- Long-term use may increase risk of bone fractures
- May affect how other medicines work - check with your pharmacist
- Tell your doctor if you have liver problems
Get medical help urgently if…
- You have difficulty swallowing
- You vomit blood or have blood in your stool
- You lose weight without trying
- You have severe stomach pain
Call NHS 111 for urgent advice, or 999 if someone is seriously unwell.
Before you act on anything here
This page is general information, written to help you understand — it is not personal medical advice and it cannot tell you what is right for you. Talk to your own GP, pharmacist or nurse about your own health.
- Need help now but it's not an emergency? Call NHS 111 or use 111.nhs.uk.
- Emergency? Call 999 or go to A&E.