Famotidine

Stomach and reflux

Also known as Pepcid

Famotidine reduces stomach acid by blocking histamine, one of the signals that tells your stomach to make acid. It works faster than medicines like omeprazole — usually within an hour — which makes it a good on-demand option for heartburn you can see coming, like before a spicy dinner. It's generally gentle and easy on most people.

How to take it

When

For prescription use, take it exactly as prescribed. For occasional heartburn, it can be taken when symptoms start or shortly before a meal you expect trouble from.

Food

With or without food — either is fine.

Avoid

If you're using it over the counter, don't take more than the label allows in 24 hours.

Good to know

If you're reaching for it most days or heartburn keeps coming back for more than two weeks, stop treating it yourself and see a doctor.

Missed a dose?

If you take it on a schedule and miss a dose, take it when you remember — unless the next dose is close, in which case skip it. Never take a double dose.

Common side effects

Headache
Dizziness
Constipation or diarrhea
Dry mouth

Call a doctor if

Black, tarry stools or vomiting blood — get help now.
Heartburn with chest pain that spreads to your arm, neck, or jaw, or with shortness of breath — this could be your heart, not your stomach. Call emergency services.
Trouble swallowing or pain when swallowing — call your doctor.
Confusion or agitation, especially in older adults or if your kidneys don't work well — call your doctor.

Educational only. This summary is drawn from public FDA labeling and MedlinePlus and simplified for readability. Your prescription label and your pharmacist always come first — doses and instructions vary from person to person.