About omeprazole
Proton pump inhibitor
Used for
- Treats heartburn and gastro-oesophageal reflux disease
- Treats stomach and duodenal ulcers
- Helps treat Helicobacter pylori with antibiotics
- Prevents ulcers linked to anti-inflammatory medicines
Usual adult dose
Usually 20 mg once daily; dose and duration depend on the condition.
Usual dose in children
For reflux or ulcers, commonly 10–20 mg once daily in children aged 1 year or older; specialist guidance is needed.
Common side effects
- Headache
- Stomach pain, nausea, diarrhoea, or constipation
- Long-term use may lower magnesium or vitamin B12
- Rarely, severe allergic or skin reactions
Important warnings
- Seek assessment for trouble swallowing, unexplained weight loss, vomiting blood, or black stools.
- Long-term use may increase fracture and certain infection risks.
- Rarely causes kidney inflammation or severe persistent diarrhoea.
- Can mask symptoms of stomach cancer.
Pregnancy
Generally considered usable when needed, but discuss use with a healthcare professional.
Breastfeeding
Small amounts enter milk; use is generally considered compatible when needed.
Interactions
- Clopidogrel: omeprazole may reduce its effectiveness.
- Warfarin: may alter blood-thinning effect; monitoring may be needed.
- Some HIV medicines, including nelfinavir, should not be combined.
- May affect absorption of medicines such as ketoconazole and iron.
AI-generated from general medical knowledge, not from this product's official leaflet. It may be incomplete or out of date. Not medical advice — ask a pharmacist or doctor before making any decision.