Famotidine is known as an H2 histamine blocker. It works by reducing the amount of acid in your stomach. It is used to prevent and treat heartburn and other symptoms caused by too much acid in the stomach (acid indigestion).

Follow all directions on the product package. If you are uncertain about any of the information, consult your doctor or pharmacist.

Take this drug as needed to stop/prevent heartburn and indigestion, or as directed by your doctor. Chew 1 tablet completely and swallow. Do not swallow whole. You may take famotidine with or without food. Do not take more than 2 tablets in 24 hours unless directed by your doctor.

To prevent heartburn and acid indigestion, take famotidine 10 to 60 minutes before eating food or drinking beverages that can cause indigestion.

Stop taking this medication and call your doctor promptly if your symptoms continue after you begin taking it, or if they do not improve after you have been taking this medication for 14 days in a row. Do not take this medication for more than 14 days in a row without talking with your doctor.

Headache, dizziness, constipation, or diarrhea may occur. If any of these effects persist or worsen, tell your doctor or pharmacist promptly.

If your doctor has directed you to use this medication, remember that he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

Tell your doctor immediately if any of these rare but very serious side effects occur: easy bruising/bleeding, fast/slow/irregular heartbeat, signs of infection (such as fever, persistent sore throat, cough), mental/mood changes (such as restlessness, confusion, depression, hallucinations), seizure.

A very serious allergic reaction to this drug is unlikely, but seek immediate medical attention if it occurs. Symptoms of a serious allergic reaction include: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

In the US -

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

Before taking famotidine, tell your doctor or pharmacist if you are allergic to it; or to other acid blockers (such as cimetidine, ranitidine); or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

If you have the following health problem, consult your doctor or pharmacist before using this medication: kidney problems.

Some symptoms of heartburn may actually be signs of a more serious condition. Tell your doctor immediately if you have: chest pain or shoulder/jaw pain (especially with trouble breathing), heartburn for longer than 3 months, heartburn combined with lightheadedness/sweating/dizziness, nausea/vomiting, pain spreading to arms/neck/shoulders, persistent stomach pain, black stools, difficult/painful swallowing, unexplained weight loss, vomit that is bloody or looks like coffee grounds.

Do not use this medication in children younger than 12 unless directed by the doctor.

During pregnancy, this medication should only be used if clearly needed. Discuss the risks and benefits with your doctor. Tell your doctor if you are pregnant before using this medication.

This drug passes into breast milk. Consult your doctor before breast-feeding.

Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.

Since famotidine reduces the amount of acid in your stomach, it may also change the absorption of certain medications and affect how they work. Some examples of affected drugs include atazanavir, dasatinib, delavirdine, certain azole antifungals (such as itraconazole, ketoconazole), among others. Ask your doctor or pharmacist if any of the medications you take are affected by famotidine and how to manage this interaction.

Check the labels on all your medicines because they may contain aspirin or aspirin-like NSAIDs (such as ibuprofen, naproxen) that can cause stomach irritation/ulcers. However, if your doctor has directed you to take low-dose aspirin for heart attack or stroke prevention (usually at dosages of 81-325 milligrams a day), you should continue taking the aspirin unless your doctor instructs you otherwise. Ask your pharmacist about using those products safely.

This medication and similar acid blockers (such as cimetidine, ranitidine) are available both over-the-counter and by prescription. Do not take them at the same time.

If overdose is suspected, contact a poison control center or emergency room immediately. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center.

Lifestyle changes such as stress reduction programs, stopping smoking, limiting alcohol, and diet changes (such as avoiding caffeine, certain spices) may help this medication work better. Talk to your doctor or pharmacist about lifestyle changes that might benefit you.

Not applicable.

Store at room temperature between 68-77 degrees F (20-25 degrees C) away from light and moisture. Do not store in the bathroom. Keep all medicines away from children and pets.

Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company for more details about how to safely discard your product.

Information last revised March 2013. Copyright(c) 2013 First Databank, Inc.