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Generic Name

famotidine (fa MOH te deen)


Trade Name

Pepcid (10mg. AC,20 mg.,40 mg.)
Pepcid is also available as an Oral Suspension.
Pepcid AC is available over-the-counter.
This drug is not available in a generic form.


What is famotidine?

This drug is one of the H2 blockers. It partially blocks the production of acid in stomach cells. Since stomach acid plays an important role in causing ulcers and other tissue injury, the drug has been very helpful in treating these conditions.


What is it used for?

Famotidine can be effective in treating the following conditions:

  • Healing and prevention of peptic ulcers in the stomach or duodenum
  • Reflux of acid into the esophagus (Gastroesophageal Reflux Disease)
  • Hyperacidity
  • Zollinger-Ellison Syndrome – a rare condition where large amounts of acid pour from the stomach. However, there are now much more effective medications for this condition.


How do I take it?

Follow your physician’s instructions carefully. Famotidine may be taken on an empty stomach or with food to prevent stomach upset. Store in a tightly closed container away from light. Keep all medications away from children. Never share your medications with anyone else.


What do I do for a missed dose?

If you miss a dose of this medicine, take it as soon as possible. If it is almost time for your next dose, skip the missed dose and return to your regular schedule. Do not double up on this medication.


Are there interactions with food or beverages?

There are no known interactions with any food or alcohol. Alcohol and caffeine, which is found in coffee, tea, cola and chocolate, both stimulate stomach acid production and may worsen ulcer symptoms.


Are there interactions with other drugs?

An interaction generally means that one drug may increase or decrease the effect of another drug. Also, the more medications a person takes, the more likely there will be a drug interaction.

Interactions with this drug may occur with the following:

  • itraconazole (Sporanox)
  • sucralfate (Carafate)
  • arthritis medications (ibuprofen, Advil, Lodine, many others)
  • ketoconazole (Nizoral)
  • antacids


Is there a problem if I have another disorder or disease?

At times, a drug may have a different or enhanced effect when other diseases are present. At other times, the drug may worsen or effect another disease. This drug is partly metabolized in the liver and excreted through the kidneys. Your physician should know if you have severe liver or kidney disease.


What about allergies?

People who have known allergies or asthma may be at an increased risk for a reaction from any new medication. The physician should always know a patient’s allergy history. Signs of an allergic reaction are skin rash, itching and hives. Of course, a person should not take famotidine if there has been a previous reaction to this or other H2 blockers.


What if I’m pregnant, considering pregnancy or breast-feeding?

Most females now know that, if possible, no drug, including alcohol, should be taken during pregnancy or lactation. The potential danger, of course, is an injury to the baby. However, some drugs are much safer than others in this regard. So, the FDA has a grading system for each drug which reflects what is known medically. It ranks drugs from A, where medical studies show no evidence for danger to the fetus or mother, to B, C, D and X, where the medical evidence indicates that the risk to the fetus outweighs any benefit to the mother. Famotidine is ranked B. Always consult your physician before taking any drug during or when planning pregnancy.


What are the effects on sexual function?

In rare cases, famotidine can cause loss of libido and impotence.


Are there other precautions?

Famotidine may cause drowsiness or dizziness. Do not drive or operate hazardous machinery until the effect of the drug has been determined. Do not use over-the-counter doses for more than 2 weeks without physician approval.


How long is it safe to take famotidine?

Continual use on a regular schedule for 4 to 6 weeks will determine the effectiveness of famotidine in healing peptic ulcer disease. Regular use for 6 to12 weeks is needed to heal the esophagus when used to treat GERD. Long-term use of months to years for prevention of gastric problems is generally safe but does require periodic physician supervision.


How about side effects?

Adverse reactions can occur with any drug, even over-the-counter medications. Some of these are mild such as a stomach upset, which may be avoided by taking the medication with food. Minor reactions may go away on their own but if they persist, contact the physician. For major reactions, the patient should contact the physician immediately.

For famotidine, the following are the observed side effects:


  • headache
  • dizziness
  • constipation
  • diarrhea


  • fever
  • swelling or yellowing of eyes
  • abnormal skin bruising
  • confusion
  • agitation


A physician’s comment…

The entire field of healing ulcers has changed considerably since it was discovered that most ulcers are caused by the bacteria, Helicobacter pylori, or by arthritis or pain medications like aspirin, Advil, Motrin and Naprosyn. Now ulcers can be cured by antibiotics and drugs are no longer needed to prevent ulcers from recurring. However, this drug can still be very useful in just plain hyperacidity and especially in reflux of acid into the esophagus- gastroesophageal reflux disease (GERD).