Sounds like 'fa-mot-uh-deen'

Famotidine is used to treat problems affecting the stomach and gut, such as indigestion, reflux and ulcers. Find out how to take it safely and possible side effects.

Type of medicine

Also called

  • Medicine to reduce stomach acid
  • Pepzan

What is famotidine?

Famotidine reduces the amount of acid produced in your stomach. It is used to treat a number of conditions associated with high stomach acid affecting your stomach and gut, such as indigestion, reflux and ulcers.

In New Zealand famotidine is available as tablets (20 mg and 40 mg) and can be given as an injection in the hospital.


  • The usual dose of famotidine for reflux is 20 mg 2 times a day.
  • For some people, 20 mg a day is enough.
  • Other people may need a higher dose of 40 mg 2 times a day.
  • It is best to take the lowest effective dose for the shortest possible time.
  • Your doctor will advise you how long to take famotidine for (usually for 4 to 8 weeks). Some people may need to take it for longer.
  • The pharmacy label on your medicine will tell you how much famotidine to take, how often to take it and any special instructions.

How to take famotidine

Timing: Take famotidine at the same times each day. Famotidine is usually taken 2 times a day, but some people may only need to take it once a day. Your doctor will tell you how often to take it.
Swallow the tablet whole with a glass of water. Famotidine can be taken with or without food.
Missed dose: If you forget to take your dose, take it as soon as you remember. But if it is nearly time for your next dose, just take the next dose at the right time. Do not take double the dose.

Precautions before starting famotidine

  • Are you pregnant, planning to get pregnant or breastfeeding?
  • Do you have problems with your kidneys?
  • Are taking any other medicines? This includes any medicines that you can buy without a prescription, as well as herbal and complementary medicines.

If so, it’s important that you tell your doctor or pharmacist before you start famotidine. Sometimes a medicine isn’t suitable for a person with certain conditions, or it can only be used with extra care.

What are the side effects of famotidine?

Like all medicines famotidine can cause side effects, although not everyone gets them. Often side effects improve as your body adjusts to the new medicine.

Side effects

What should I do?

  • Stomach upset, feeling sick, dizziness
  • Feeling bloated, gas in your abdomen (tummy)
  • Runny poo (mild diarrhoea)
  • These are quite common when you first start taking famotidine.
  • Tell your doctor if troublesome.


  • Signs of problems with your liver such as as severe tummy pain, yellowing of your eyes and skin, dark pee.
  • Tell your doctor immediately or phone Healthline 0800 611 116.


  • Worsening stomach problems, such as really bad stomach pain, blood in your stool or black stools, vomiting blood or dark-coloured vomit
  • Tell your doctor immediately or phone Healthline 0800 611 116.
Did you know that you can report a side effect to a medicine to CARM (Centre for Adverse Reactions Monitoring)? Report a side effect to a product

Learn more

Famotidine NZ Formulary Patient Information


  1. Famotidine NZ Formulary
Credits: Sandra Ponen, Pharmacist. Reviewed By: Angela Lambie, Pharmacist, Auckland