Famotidine

pronounced as (fa moe' ti deen)

Brand Name(s): Fluxid®, Pepcid®, Pepcid® AC, Pepcid®RPD ¶, Duexis®(as a combination product containing Famotidine, Ibuprofen) ¶, Pepcid® Complete (as a combination product containing Calcium Carbonate, Famotidine, Magnesium Hydroxide), also available generically
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Why is this medicine prescribed?

Prescription famotidine is used to

  • treat ulcers (sores in the lining of the stomach or intestine)
  • treat gastroesophageal reflux disease (GERD; a condition where stomach acid flows back into the esophagus (tube between the stomach and throat))
  • treat conditions where the stomach produces too much acid, such as Zollinger-Ellison syndrome
  • treat and prevent heartburn

Famotidine is in a class of medications called H 2 blockers. It works by decreasing the amount of acid made in the stomach.

Are there other uses for this medicine?

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

How should this medicine be used?

Famotidine comes as a tablet, chewable tablet, and a suspension (liquid) to take by mouth. Take once daily at bedtime or two to four times a day.Take famotidine exactly as directed.

Do not take more or less of it or take it more often or for a longer time than prescribed by your doctor.

Shake the liquid well for 5 to 10 seconds before each use to mix the medicine evenly.

Swallow the tablets with a full glass of water.

Thoroughly chew the chewable tablets before swallowing them. Swallow the chewed tablet with a full glass of water.

Do not take more than two tablets, or chewable tablets of over-the-counter famotidine in 24 hours and do not take over-the-counter famotidine for longer than 2 weeks unless your doctor tells you that you should. If symptoms of heartburn, acid indigestion, or sour stomach last longer than 2 weeks, stop taking over-the-counter famotidine and call your doctor.

What special precautions should I follow?

Before taking famotidine,

  • tell your doctor or pharmacist if you are allergic to this medication, any part of this medication, or any other medications, foods or substances. Tell your doctor or pharmacist about the allergy and what symptoms you had.
  • you should know that some medications should not be taken with famotidine. Other medications may cause dosing changes or extra monitoring when taken with famotidine. Make sure you have discussed any medications you are currently taking or plan to take before starting famotidine with your doctor and pharmacist. Before starting, stopping, or changing any medications while taking famotidine, please get the advice of your doctor or pharmacist.
  • you should know that the following nonprescription products may interact with famotidine: other medications for heartburn. Be sure to let your doctor and pharmacist know that you are taking these medications before you start taking famotidine. Do not start any of these medications while taking famotidine without discussing with your healthcare provider.
  • tell your doctor if you have phenylketonuria (PKU, a condition in which a special diet must be followed to prevent damage to your brain), and if you have or have ever had trouble swallowing or kidney disease.
  • tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while taking famotidine, call your doctor.
  • if you are 65 years of age or older, do not take this medication for a longer period of time than recommended on the product label or by your doctor.

What special dietary instructions should I follow?

Unless your doctor tells you otherwise, continue your normal diet.

What should I do if I forget to take a dose?

If you forget a dose of prescription famotidine, take the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.

What should I do in case of overdose?

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at https://www.poisonhelp.org/help . If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

What side effects can this medicine cause?

Famotidine may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

  • headache
  • dizziness
  • constipation
  • diarrhea
  • fussiness (in babies who take famotidine)

Some side effects can be serious. The following symptoms are uncommon, but if you experience any of them call your doctor immediately:

  • hives; skin rash; itching; swelling of the face, throat, tongue, lips, eyes, hands, feet, ankles, or lower legs;hoarseness; difficulty breathing or swallowing

Famotidine may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online ( https://www.fda.gov/Safety/MedWatch ) or by phone ( 1-800-332-1088).

What should I know about storage and disposal of this medication?

Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom). Do not allow the liquid to freeze. Dispose of unused famotidine liquid after 30 days.

Dispose of unneeded medications in a way so that pets, children, and other people cannot take them. Do not flush this medication down the toilet. Use a medicine take-back program. Talk to your pharmacist about take-back programs in your community. Visit the FDA's Safe Disposal of Medicines website https://goo.gl/c4Rm4p for more information. Keep all medication out of sight and reach of children as many containers are not child-resistant. Always lock safety caps. Place the medication in a safe location – one that is up and away and out of their sight and reach. https://www.upandaway.org

What other information should I know?

Keep all appointments with your doctor.

Do not let anyone else take your medicine. Ask your pharmacist any questions you have about refilling your prescription.

Keep a written list of all of the prescription and nonprescription (over-the-counter) medicines, vitamins, minerals, and dietary supplements you are taking. Bring this list with you each time you visit a doctor or if you are admitted to the hospital. You should carry the list with you in case of emergencies.

This branded product is no longer on the market. Generic alternatives may be available.

This report on medications is for your information only, and is not considered individual patient advice. Because of the changing nature of drug information, please consult your physician or pharmacist about specific clinical use.

The American Society of Health-System Pharmacists, Inc. represents that the information provided hereunder was formulated with a reasonable standard of care, and in conformity with professional standards in the field. The American Society of Health-System Pharmacists, Inc. makes no representations or warranties, express or implied, including, but not limited to, any implied warranty of merchantability and/or fitness for a particular purpose, with respect to such information and specifically disclaims all such warranties. Users are advised that decisions regarding drug therapy are complex medical decisions requiring the independent, informed decision of an appropriate health care professional, and the information is provided for informational purposes only. The entire monograph for a drug should be reviewed for a thorough understanding of the drug's actions, uses and side effects. The American Society of Health-System Pharmacists, Inc. does not endorse or recommend the use of any drug. The information is not a substitute for medical care.

AHFS ® Patient Medication Information™. © Copyright, 2026. The American Society of Health-System Pharmacists ® , 4500 East-West Highway, Suite 900, Bethesda, Maryland. All Rights Reserved. Duplication for commercial use must be authorized by ASHP.

Selected Revisions: October 15, 2026.