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).
Check the ingredients on the label even if you have used the product before. The manufacturer may have changed the ingredients. Also, products with similar names may contain different ingredients meant for different purposes. Taking the wrong product could harm you.
To treat heartburn and acid indigestion, take 1 tablet or capsule with a glass of water as needed, unless otherwise directed by your doctor. Swallow the tablets and capsules whole without chewing. If you are using the chewable tablets, chew completely and swallow one tablet as needed. Do not swallow whole. Famotidine can be taken with or without food.
To prevent heartburn and acid indigestion, take famotidine 15-60 minutes before eating food or drinking beverages that can cause indigestion.
Do not take more than 2 tablets in 24 hours unless directed by your doctor. Follow all directions on the product package. If you are uncertain about any of the information, consult your doctor or pharmacist.
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.
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 (e.g., fever, persistent sore throat, cough), mental/mood changes (e.g., 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 (e.g., 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.
Some symptoms may actually be signs of a more serious condition. Get medical help right away if you have: heartburn with lightheadedness/sweating/dizziness, chest/jaw/arm/shoulder pain (especially with shortness of breath, unusual sweating), unexplained weight loss.
In addition, before you self-treat with this medication, get medical help right away if you have any of these signs of a serious condition: trouble/pain swallowing food, bloody vomit, vomit that looks like coffee grounds, bloody/black stools, heartburn for over 3 months, frequent chest pain, frequent wheezing (especially with heartburn), nausea/vomiting, stomach pain.
This chewable form of this medication contains aspartame. If you have phenylketonuria (PKU) or any other condition that requires you to restrict your intake of aspartame (or phenylalanine), consult your doctor or pharmacist regarding the safe use of this medication.
Do not use this medication in children younger than 12 unless directed by the doctor.
Older adults may be more sensitive to the side effects of this drug, especially confusion.
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.
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), pazopanib, 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 (e.g., ibuprofen, naproxen) that can cause stomach irritation/ulcers. Ask your pharmacist about the safe use of those products. Low-dose aspirin, as prescribed by your doctor for specific medical reasons such as heart attack or stroke prevention (usually at dosages of 81-325 milligrams per day), should be continued. Consult your doctor or pharmacist for more details.
This medication and similar acid blockers (e.g., 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 (e.g., avoiding caffeine, certain spices) may increase the effectiveness of this medication. Talk to your doctor or pharmacist about lifestyle changes that might benefit you.
Store at room temperature between 68-86 degrees F (20-30 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 June 2014. Copyright(c) 2014 First Databank, Inc.
With WebMD's Medicine Cabinet, you can check interactions with drugs.Go to medicine cabinet