Health Library

Famotidine (By mouth)

Famotidine (fam-OH-ti-deen)

Treats ulcers, gastroesophageal reflux disease (GERD), and conditions that cause the stomach to produce too much acid. Also treats heartburn caused by acid indigestion.

Brand Name(s):

Acid Controller, Acid Reducer, Foster&Thrive Acid Reducer, Good Neighbor Pharmacy Acid Reducer, Good Sense Acid Reducer, Heartburn Relief, Leader Acid Reducer, Pepcid, Pepcid AC, Sunmark Acid Reducer, TopCare Acid Reducer, Zantac 360

When This Medicine Should Not Be Used:

How to Use This Medicine:

Liquid, Tablet, Chewable Tablet, Dissolving Tablet

• Take your medicine as directed. Your dose may need to be changed several times to find what works best for you.
• Follow the instructions on the medicine label if you are using this medicine without a prescription.
• The chewable tablet must be chewed completely before you swallow it.
• If you are using the disintegrating tablet, make sure your hands are dry before you handle it. Do not open the blister pack that contains the tablet until you are ready to take it. Remove the tablet from the blister pack by peeling back the foil, then taking the tablet out. Do not push the tablet through the foil. Place the tablet in your mouth. It should melt within 2 minutes. Swallow after the tablet has melted.
• Shake the oral liquid for 5 to 10 seconds before each use. Measure the medicine with a marked measuring spoon or medicine cup.
• Missed dose: Take a dose as soon as you remember. If it is almost time for your next dose, wait until then and take a regular dose. Do not take extra medicine to make up for a missed dose.
• Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Do not freeze the oral liquid. Throw away any unused oral liquid after 1 month.

Drugs and Foods to Avoid:

Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.

• Some medicines can affect how famotidine works. Tell your doctor if you are using cefditoren, dasatinib, delavirdine, fosamprenavir, or tizanidine.

Warnings While Using This Medicine:

• Tell your doctor if you are pregnant or breastfeeding, or if you have kidney disease, liver disease, or stomach cancer.
• This medicine may cause changes in your heart rhythm (including QT prolongation).
• Some brands or forms of this medicine may contain phenylalanine (aspartame). If you have phenylketonuria (PKU), talk to your doctor before using this medicine.
• Call your doctor if your symptoms do not improve or if they get worse.
• Your doctor will do lab tests at regular visits to check on the effects of this medicine. Keep all appointments.
• Keep all medicine out of the reach of children. Never share your medicine with anyone.

Possible Side Effects While Using This Medicine:

Call your doctor right away if you notice any of these side effects:

• Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing
• Agitation, confusion, seizures
• Blistering, peeling, red skin rash
• Dark urine or pale stools, yellow eyes or skin
• Fainting, dizziness, lightheadedness
• Fast, pounding, or uneven heartbeat
• Fever, chills, cough, sore throat, body aches
• Unusual bleeding, bruising, or weakness

If you notice these less serious side effects, talk with your doctor:

• Constipation, diarrhea, upset stomach
• Headache
• Nausea, vomiting

If you notice other side effects that you think are caused by this medicine, tell your doctor

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088

Last Updated: 9/6/2024