SingHealth Duke-NUS Academic Medical Centre will NEVER ask you to transfer money over a call. If in doubt, call the 24/7 ScamShield helpline at 1799, or visit the ScamShield website at www.scamshield.gov.sg.
Omeprazole is used to treat various conditions of the gastrointestinal (stomach and intestines) tract including:
You can also find out about this medication by watching these videos:
They are available in English, 中文, Melayu and தமிழ்: Omeprazole
Do not stop taking your medication without checking with your healthcare professional.
If you forget to take a dose, take it as soon as you remember. Then take your next dose at the usual time. Do not take two doses to make up for the missed dose.
Inform your healthcare professional if:
Inform your healthcare professional if you are taking or intend to take any other medication, supplements, traditional medications or herbal remedies.
This includes:
Side effects of omeprazole include headaches, gastrointestinal side effects (e.g. abdominal pain, diarrhoea, nausea and vomiting and wind).
The symptoms of a drug allergy include one or more of the following:
Furthermore, unusual symptoms such as muscle spasms (tetany), palpitations, dizziness and seizures may be a sign of low magnesium in the body.
If you experience any of these symptoms, you should stop your medicine and see your healthcare professional immediately.
You can also find out about drug allergies by watching these videos:
They are available in English, 中文, Melayu and தமிழ்: Drug Allergies
Store in a cool and dry place, away from direct sunlight. Keep this medication away from children.
Pack this medication into a black trash bag and seal it tightly before throwing into the rubbish chute or bin.
The length of treatment with omeprazole depends on your condition and how well you respond to the medication.
For heartburn and reflux symptoms:
· Most people experience relief within the first few days to weeks of starting omeprazole. Your doctor will usually prescribe this medication for 4-8 weeks initially to allow healing.
For ulcer treatment:
· Treatment typically lasts 4-8 weeks, depending on the type and severity of the ulcer.
Some people may need to stay on omeprazole for a long time to manage their condition, whilst others may only need this medication for a short period.
Do not stop taking or change your dose without checking with your healthcare professional. If you have been taking omeprazole for more than a few months, discuss with your healthcare professional whether you still need it. This ensures the medication remains suitable and beneficial for you.
Important reminders:
• If your healthcare professional suggests reducing the dose, this may be done gradually to minimise the return of symptoms.
• It is normal for some people to experience temporary return of symptoms when stopping or lowering the dose - this usually improves within a few weeks.
• During this time, your healthcare professional may suggest lifestyle measures such as avoiding triggers (spicy, citrus, fatty or fried foods), eating smaller meals, or using antacids for temporary relief.
• Keep track of your symptoms and inform your healthcare professional of any changes.
Disclaimers
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 (NHG Health, 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.
Use Medicine Order Service on HealthBuddy.
Get reminders and chart progress on HealthBuddy.
© 2026 Singapore Health Services Pte Ltd. All Rights Reserved.