What it is used for
- Heartburn and indigestion (historically)
- Acid reflux (GERD)
- Stomach and duodenal ulcers
How it works
Ranitidine blocks histamine signals (at H2 receptors) that tell the stomach to make acid, so it lowers acid production and eases acid-related symptoms.
How it is taken
Was available as tablets, effervescent tablets, oral liquid, and injection. Importantly, many regulators (including in the US, UK, EU and elsewhere) withdrew or suspended ranitidine products after an impurity concern, so it is no longer widely available; alternatives are usually recommended. If you have old supplies, do not use them without checking with a pharmacist, and follow only current professional advice.
No doses here on purpose. The right strength and schedule depend on you — only a doctor or pharmacist should set them. Always follow your prescription and the label.
Common side effects
- Headache
- Constipation or diarrhea
- Dizziness
- Stomach discomfort
Serious effects — get help
- Severe allergic reaction (swelling, breathing trouble)
- Yellowing of skin or eyes (possible liver effect)
- Confusion or fast/irregular heartbeat
- Unusual bruising or bleeding
If a reaction is severe — for example trouble breathing, swelling of the face or throat, or collapse — go to the nearest emergency room now or call your local emergency number. Do not wait for an online consultation.
Interactions to watch
- Drugs needing stomach acid for absorption (some antifungals)
- Warfarin
- Certain other medicines whose levels depend on stomach acidity
Who should take care
- Because of the withdrawal, ask a pharmacist about a suitable alternative such as another H2 blocker or a PPI
- Tell your clinician about kidney or liver problems
- Discuss pregnancy or breastfeeding before using any acid medicine
- Do not self-treat persistent or alarm symptoms; get them assessed