About famotidine
Histamine-2 receptor blocker
Used for
- Treats heartburn and acid indigestion
- Helps prevent heartburn from food or drink
- Treats stomach and duodenal ulcers
- Treats gastroesophageal reflux disease
Usual adult dose
For occasional heartburn: 10–20 mg when symptoms occur or 10–60 minutes before a trigger; maximum 40 mg daily without medical supervision.
Usual dose in children
For children 12 years and older: usual over-the-counter doses; younger children require clinician-directed dosing.
Common side effects
- Headache
- Dizziness
- Constipation or diarrhea
- Nausea
Important warnings
- Kidney disease may require a lower dose.
- Persistent symptoms, trouble swallowing, vomiting blood, or black stools need medical evaluation.
- Long-term or high-dose use should be medically supervised.
- Some heartburn products combine famotidine with other medicines; check the label.
Pregnancy
Generally considered low risk when needed; use during pregnancy should be discussed with a healthcare professional.
Breastfeeding
Small amounts enter breast milk; generally considered compatible at usual doses.
Interactions
- May reduce absorption of medicines needing stomach acid, such as atazanavir or dasatinib.
- May affect absorption of ketoconazole; separate doses as directed.
- Probenecid may increase famotidine levels.
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 It may be incomplete or out of date.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.