Pepcid is a histamine-2 blocker that works by decreasing the amount of acid the stomach produces.

Pepcid is used to treat and prevent ulcers in the stomach and intestines. It also treats conditions in which the stomach produces too much acid, such as Zollinger-Ellison syndrome.

Pepcid also treats gastroesophageal reflux disease (GERD) and other conditions in which acid backs up from the stomach into the esophagus, causing heartburn.

Before taking Pepcid, tell your doctor if you have kidney or liver disease, a history of Long QT syndrome, stomach cancer or other problems, or asthma, COPD, or other breathing problems.

Pepcid may be only part of a complete program of treatment that also includes changes in diet or lifestyle habits. Follow your doctor's instructions very closely.

Heartburn is often confused with the first symptoms of a heart attack. Seek emergency medical attention if you have chest pain or heavy feeling, pain spreading to the arm or shoulder, nausea, sweating, and a general ill feeling.

You should not use Pepcid if you are allergic to famotidine or similar medicines such as ranitidine (Zantac), cimetidine (Tagamet), or nizatidine (Axid).

Before taking this medicine

Heartburn can mimic early symptoms of a heart attack. Get emergency medical help if you have chest pain that spreads to your jaw or shoulder and you feel anxious or light-headed.

To make sure Pepcid is safe for you, tell your doctor or pharmacist if you have ever had:

• kidney disease;

• liver disease;

• cancer stomach; or

• long QT syndrome (in you or a family member).

Ask a doctor before using Pepcid if you are pregnant or breastfeeding.

Use Pepcid exactly as directed on the label, or as prescribed by your doctor.

You may take this medicine with or without food.

Measure liquid medicine carefully. Use the dosing syringe provided, or use a medicine dose-measuring device (not a kitchen spoon).

Most ulcers heal within 4 weeks of famotidine treatment, but it may take up to 8 weeks of using this medicine before your ulcer heals. Keep using the medication as directed.

Call your doctor if the condition you are treating with famotidine does not improve, or if it gets worse.

Pepcid may be only part of a complete program of treatment that also includes changes in diet or lifestyle habits. Follow all instructions of your doctor or dietitian.

Store at room temperature away from moisture, heat, and light. Do not allow the liquid medicine to freeze.

Throw away any unused liquid that is older than 30 days.

Heartburn can mimic early symptoms of a heart attack. Get emergency medical help if you have chest pain that spreads to your jaw or shoulder and you feel anxious or light-headed.

To make sure Pepcid is safe for you, tell your doctor or pharmacist if you have ever had:

• kidney disease;

• liver disease;

• cancer stomach; or

• long QT syndrome (in you or a family member).

Ask a doctor before using Pepcid if you are pregnant or breastfeeding.

Take the medicine as soon as you can, but skip the missed dose if it is almost time for your next dose. Do not take two doses at one time.

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

Drinking alcohol may increase the risk of damage to your stomach.

Avoid taking other stomach acid reducers unless your doctor has told you to. However, you may take an antacid (such as Maalox, Mylanta, Gaviscon, Milk of Magnesia, Rolaids, or Tums) with famotidine.

Get emergency medical help if you have any signs of an allergic reaction to Pepcid: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Stop using this medicine and call your doctor at once if you have:

• confusion, hallucinations, agitation, lack of energy;

• a seizure;

• fast or pounding heartbeats, sudden dizziness (like you might pass out); or

• unexplained muscle pain, tenderness, or weakness especially if you also have fever, unusual tiredness, and dark colored urine.

Some side effects may be more likely in older adults and in people who have severe kidney disease.

Common Pepcid side effects may include:

• headache;

• dizziness; or

• constipation or diarrhea.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Famotidine can make it harder for your body to absorb other medicines you take by mouth. Tell your doctor if you are taking:

• cefditoren;

• dasatinib;

• delavirdine;

• fosamprenavir; or

• tizanidine (if you are taking famotidine liquid).

This list is not complete. Other drugs may interact with famotidine, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.

This medicine typically works quickly, and the relief should last all day or night, though this will depend on the specific formulation you use.

Original strength Pepcid AC and Maximum Strength Pepcid AC start to work within 15 to 30 minutes. Pepcid Complete begins working in seconds.

Your length of treatment will depend on your medical condition.

Your dosage will be based on your medical condition, the formulation you use, and other factors.

Follow the instructions on the product label carefully when using this medicine.

Doctors sometimes use Pepcid for other indications, such as to:

• Reduce gastrointestinal side effects associated with nonsteroidal anti-inflammatory drugs (NSAIDs)
• Prevent stress ulcers in critically ill patients
• Relieve symptoms of gastritis
• Prevent aspiration during surgical procedures
• Help symptoms of chronic hives

Pepcid may also be used for conditions that aren’t listed in this medical guide.