Common uses

Prescription famotidine is used to 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.

Before using

Before taking this medication, tell your doctor if you have
• kidney disease; or
• liver disease;
• trouble or pain swallowing food;
• vomiting with blood; or
• bloody or black stools.
You may not be able to take Pepcid, or you may require a dosage adjustment or special monitoring during treatment if you have any of the conditions listed above.
The Pepcid RPD orally disintegrating tablets contain 1.05 mg phenylalanine per 20 mg tablet and 2.10 mg phenylalanine per 40 mg oral tablet. Individuals with phenylketonuria may need to monitor their intake of this additive.
Pepcid is in the FDA pregnancy category B. This means that it is not expected to be harmful to an unborn baby. Do not take this medication without first talking to your doctor if you are pregnant or could become pregnant during treatment. Famotidine passes into breast milk. It is not known whether this medication will harm a nursing infant. Do not take this medication without first talking to your doctor if you are breast-feeding a baby.


Directions

The recommended adult oral dose for treating duodenal ulcers is 40 mg once daily at bedtime or 20 mg twice daily. Most patients heal their ulcers within 4 weeks. The regimen for maintenance therapy after the ulcers are healed is 20 mg once a day at bedtime.
The recommended adult oral dose for treating gastric ulcer is 40 mg once a day at bedtime, and esophagitis is treated with 20-40 mg twice daily for 6-12 weeks. Zollinger-Ellison syndrome is treated with 20 mg every 6 hours.
Heartburn due to GERD is treated with 10-20 mg daily.

Cautions

• This medicine can mask the symptoms of stomach cancer and therefore delay diagnosis of this condition. For this reason, when a stomach ulcer is suspected, your doctor should exclude the possibility of stomach cancer before you start treatment with this medicine, particularly if you are middle aged or older and have new or recently changed symptoms.
• The safety and efficacy of this medicine in children has not been studied by the manufacturer.
Do not stop taking this medication without first talking to your doctor. It may take up to 8 weeks for an ulcer to heal. Do not take antacids within 1 hour of taking this medication. Antacids may decrease the effectiveness of Pepcid.

Possible side effects

Medicines and their possible side effects can affect individual people in different ways. The following are some of the side effects that are known to be associated with this medicine. Because a side effect is stated here, it does not mean that all people using this medicine will experience that or any side effect.
• Depression
• Confusion
• Muscle cramps
• Disturbances of the gut such as diarrhoea, constipation, nausea, vomiting or abdominal pain
• An extreme allergic reaction (anaphylaxis)
• Loss of appetite
• Skin reactions such as rash and itch
• Anxiety and agitation
• Jaundice caused by blockage of bile flow (cholestatic jaundice)
• Headache
• Dizziness
• Dry mouth
• Fatigue
• Abnormal enlargement of breasts in men (gynaecomastia)
The side effects listed above may not include all of the side effects reported by the drug's manufacturer.

For more information about any other possible risks associated with this medicine, please read the information provided with the medicine or consult your doctor or pharmacist.

If you take too much

The adverse reactions in overdose cases are similar to the adverse reactions encountered in normal clinical experience. Oral doses of up to 640 mg/day have been given to adult patients with pathological hypersecretory conditions with no serious adverse effects. In the event of overdosage, treatment should be symptomatic and supportive. Unabsorbed material should be removed from the gastrointestinal tract, the patient should be monitored, and supportive therapy should be employed.

Additional information

According to Pepcid Complete labeling, the following tips can assist with managing heartburn:

• Do not lie flat or bend over soon after eating.
• Do not eat late at night, or just before bedtime.
• Certain foods or drinks are more likely to cause heartburn, such as rich, spicy, fatty, and fried foods, chocolate, caffeine, alcohol, and even some fruits and vegetables.
• Eat slowly and do not eat big meals.
• Maintain healthy body weight.
• Do not smoke.
• Raise the head of your bed.
• Wear loose fitting clothing around your stomach.

Drug interactions

No drug interactions have been identified. Studies with famotidine in man, in animal models, and in vitro have shown no significant interference with the disposition of compounds metabolized by the hepatic microsomal enzymes, e.g., cytochrome P450 system. Compounds tested in man include warfarin, theophylline, phenytoin, diazepam, aminopyrine and antipyrine. Indocyanine green as an index of hepatic drug extraction has been tested and no significant effects have been found.