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URL of this page: https://medlineplus.gov/druginfo/meds/a687011.html

Famotidine

pronounced as (fa moe' ti deen)

Why is this medication prescribed?

Prescription famotidine is used to treat ulcers (sores on the lining of the stomach or small intestine); gastroesophageal reflux disease (GERD, a condition in which backward flow of acid from the stomach causes heartburn and injury of the esophagus [tube that connects the mouth and stomach]); and conditions where the stomach produces too much acid, such as Zollinger-Ellison syndrome (tumors in the pancreas or small intestine that cause increased production of stomach acid). Over-the-counter famotidine is used to prevent and treat heartburn due to acid indigestion and sour stomach caused by eating or drinking certain foods or drinks. Famotidine is in a class of medications called H2 blockers. It works by decreasing the amount of acid made in the stomach.

How should this medicine be used?

Prescription famotidine comes as a tablet and a suspension (liquid) to take by mouth. It is usually taken once daily at bedtime or two to four times a day. Over-the-counter famotidine comes as a tablet, a chewable tablet, and a capsule to take by mouth. It is usually taken once or twice a day. To prevent symptoms, it is taken 15 to 60 minutes before eating foods or drinking drinks that may cause heartburn. Follow the directions on your prescription or the package label carefully, and ask your doctor or pharmacist to explain any part you do not understand. 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 and capsules 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, capsules, 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.

Other uses for this medicine

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

What special precautions should I follow?

Before taking famotidine,

  • tell your doctor and pharmacist if you are allergic to famotidine, cimetidine (Tagamet), nizatidine (Axid), ranitidine (Zantac), or any other medications.
  • tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking. Be sure to mention any other medications for heartburn. Do not take over-the-counter famotidine with any other prescription or nonprescription medications for heartburn unless a doctor tells you that you should.
  • tell your doctor if you have phenylketonuria (PKU, an inherited condition in which a special diet must be followed to prevent damage to your brain that can cause severe intellectual disability), 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.

What special dietary instructions should I follow?

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

What should I do if I forget 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.

Over-the-counter famotidine is usually taken as needed. If your doctor has told you to take over-the-counter famotidine regularly, 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 side effects can this medication 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 (http://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.

Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA's Safe Disposal of Medicines website (http://goo.gl/c4Rm4p) for more information if you do not have access to a take-back program.

It is important to keep all medication out of sight and reach of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location – one that is up and away and out of their sight and reach. http://www.upandaway.org

In case of emergency/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 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.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.

Brand names

  • Fluxid®
  • Pepcid®
  • Pepcid® AC
  • Pepcid® RPD

Brand names of combination products

  • Duexis® (containing Famotidine, Ibuprofen)
  • Pepcid® Complete (containing Calcium Carbonate, Famotidine, Magnesium Hydroxide)

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

Last Revised - 01/15/2022