About famotidine
Histamine-2 receptor blocker
Used for
- Treats stomach and duodenal ulcers
- Relieves heartburn and acid reflux
- Treats excess stomach acid, including Zollinger-Ellison syndrome
Usual adult dose
Usually 20 mg twice daily or 40 mg once daily for ulcers; reflux dosing varies by condition.
Usual dose in children
For children aged 1 year and older, dosing is weight-based and depends on the condition.
Common side effects
- Headache
- Dizziness
- Constipation or diarrhea
- Nausea
Important warnings
- Dose adjustment may be needed with kidney impairment.
- Rarely, confusion or other nervous-system effects occur, especially in older adults or people with kidney problems.
- Persistent or severe stomach symptoms need medical assessment.
- Long-term acid reduction may affect vitamin B12 absorption.
Pregnancy
Available evidence has not shown a clear increased risk, but use should be guided by a healthcare professional.
Breastfeeding
Small amounts enter breast milk; use is generally considered compatible when clinically needed.
Interactions
- May reduce absorption of medicines needing stomach acid, such as some antifungals.
- Antacids may reduce famotidine absorption if taken together.
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 It may be incomplete or out of date.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.