Famotidine (Pepcid®) for Dogs

Famotidine, also known as famotidine hydrochloride or famotidine HCl, is the generic name for a medication used to treat excessive stomach acid production, esophagitis, and gastroesophageal reflux disease (GERD). It is currently one of the most commonly-prescribed drugs in the United States and is available as both a prescription drug and over-the counter. It is typically known by the brand names “Pepcid®” and “Pepcid AC®.”

Fast Facts: What Is Famotidine (Pepcid)?

• Famotidine is an anti-ulcer drug of the histamine receptor-2 (H-2) antagonist class. Stimulation of H-2 receptors (targets) located on the cell membranes of stomach cells leads to secretion of gastric acid. The drug slows stomach acid production, allowing the ulcer time to heal. Other drugs with similar actions include ranitidine (Zantac®), nizatidine (Axid®) and cimetidine (Tagamet®).
• Use of famotidine can decrease nausea in dogs by its action on the chemoreceptor trigger zone.
• Pepcid is used to treat pets with stomach ulcers, esophagitis, gastric reflux, esophageal reflux, Helicobacter infections, and/or vomiting.
• Studies suggest that there is a diminished effect of famotidine when given on a consistent long-term basis (more than 14 days). For this reason, twice daily dosing may be recommended.

Brand Names for Famotidine

• This drug is registered and FDA approved for human use only.
• Human formulations: Pepcid (Merck), Pepcid AC, and other brand names including Act, Dyspep HB, Pepzan, Arfam, Pamacid, Peptris, Famotren, Famistine, and Fluxid.
• Veterinary formulations: None

Is Pepcid Routinely Prescribed to Pets?

This drug is not FDA approved for use in animals, but it is legally prescribed by veterinarians as an extra-label drug. Famotidine is available over-the-counter, but should not be administered unless under the supervision and guidance of a veterinarian. Pepcid is one of 15 human over-the-counter drugs considered safe for dogs.

Uses of Famotidine for Dogs

Famotidine has a number of purposes for humans, dogs, cats, and other pets:

• Famotidine is used in the treatment and prevention of stomach (gastric) and intestinal ulcers or erosions (shallow depressions in the stomach lining).
• Drugs like Pepcid are used to manage gastric reflux, also known as acid-reflux disease, a condition similar to “heartburn” in people and caused by movement of stomach acid into the lower part of the esophagus. It can help to reduce injury to the esophagus (food tube), making it a good medication for dogs with megaesophagus.
• Famotidine may be useful in the treatment of stomach inflammation caused by kidney disease or kidney failure.
• Dogs with mast cell tumors may be treated with famotidine or a related drug, since these tumors can produce large amounts of histamine.
• Famotidine is used to treat a variety of causes of nausea in dogs and sometimes prescribed to pets that have a decreased appetite. Click here to learn more about caring for a dog that won’t eat.
• Because famotidine blocks histamine, it is sometimes used in addition to other medications, such as steroids or diphenhydramine (Benadryl®), to treat an allergic reaction.
• Famotidine is used in many situations that result in stomach problems, ulcers, or diseases that cause nausea and vomiting. Examples include inflammatory bowel disease, acute pancreatitis, or infections such as canine parvoviral enteritis or helicobacter.

How Is Famotidine Supplied?

Famotidine is available in both prescription and over-the-counter formulations.

• 10 mg, 20 mg, and 40 mg tablets.
• Oral powder for suspension is supplied at 50 mg/5 ml.
• An injectable at the concentration of 20 mg/50 mL or 20 mg (2 mg/mL).

Pepcid Dosage for Dogs

Medication should never be administered without first consulting your veterinarian. Make sure to discuss proper dosage and other precautions with your veterinarian before using Pepcid for dogs. If you’re concerned about costs related to medication, learn how pet insurance may be able to help. Click here to learn more.

The typical dose of famotidine administered is 0.25 to 0.5 mg per pound (0.5 to 1.0 mg/kg) every 12 to 24 hours. There is a diminished effect when given for more than 14 consecutive days. For this reason, twice daily dosing may be recommended.

The duration of administration depends on the condition being treated, response to the medication, and the development of any adverse side effects. Be certain to complete the prescription unless specifically directed by your veterinarian. Even if your pet feels better, complete the entire treatment plan to avoid a sudden relapse.

Tablets should be stored away from light and at room temperature. Liquid formulations should be refrigerated.

Potential Side Effects of Pepcid

Call your vet if you are concerned about your pet ingesting a toxic dose of medication and if you observe any of the following side effects:

• Diarrhea
• Difficulty breathing
• Difficulty walking
• Lack of appetite
• Lethargy
• Pale gums
• Vomiting

Make sure to monitor your pet closely and observe their behavior, urination, and bowel movements to ensure they are not suffering from any of these symptoms. Contact your veterinarian immediately if you believe your pet has ingested a potentially-toxic dose of famotidine.

How to Prevent Unintended Pepcid Exposure

Curious pets are good at getting into things, and it’s always better to prevent poisoning than to treat it after the fact. Take these precautions to keep your pets from unwittingly ingesting a dangerous amount of famotidine:

• Store all medications out of the reach of pets.
• Take extra special care with pill bottles and weekly pill holders. The shape of the containers and the sounds they make when shaken can mimic toys, tempting pets into playing with them or chewing on them.
• Avoid using plastic bags to store pills. If you are traveling with medications, keep them secure. Bags can be easily chewed through and ingested.
• If you keep medications in your purse, make sure you close it, hang it up, or secure it in an area that is inaccessible to your pet.
• Encourage house guests to keep their belongings closed and medications away from your pets.

More Pet Emergency Resources

If your pet ingests Pepcid and you can’t get in touch with your vet, call your closest emergency clinic. Another option is to call a poison control hotline for pets.

The two most common are:

• Pet Poison Helpline
• ASPCA Animal Poison Control Center

FAQs About Famotidine for Dogs

What should I do if I miss giving a dose of famotidine?

If you miss giving a dose of famotidine to your dog, you can give the missed dose as soon as possible. However, if the next dose is due soon, don’t double the dose, just give the regularly scheduled dose.

What is the most important thing I should know about famotidine?

Pepcid is in a class of drugs referred to as “H2 blockers” and related to medications like cimetidine (Tagamet) and ranitidine (Zantac). Famotidine decreases the production of stomach acid. It is a fairly safe drug and overdoses are uncommon. Pepcid is commonly prescribed to dogs, cats, and other animals.

What should I discuss with my veterinarian before giving famotidine to my pet?

You should discuss the underlying issue with your veterinarian before giving your pet any medication. For example, if your dog is not eating, you should discuss potential causes and create a plan of action. It’s important to look for additional symptoms, such as vomiting, diarrhea, lethargy, blood in the vomit or stool, and any other abnormalities.

Are there alternatives to famotidine?

Alternative drugs such as omeprazole, commonly known as Prilosec®, may have superior gastric acid suppression. Depending on your dog’s clinical symptoms, alternatives like cerenia may be recommended to treat vomiting.

Can you buy famotidine over-the-counter?

Yes, you can buy famotidine over-the-counter in some sizes (10 mg is the most common).

What are contraindications to giving famotidine?

Famotidine should be used with caution in dogs with kidney and liver disease. Because it is metabolized by these organs, toxicity is possible. With that being said, famotidine is very commonly recommended, but a lower dose or frequency may be used in some dogs.

Does famotidine need to be given with food?

Ideally, famotidine should be given on an empty stomach and not with food.

What drugs interact with famotidine?

Famotidine has minimal drug interactions. However, because the primary effect of famotidine is to decrease gastric acid, the pH alteration can impact the absorption of other orally administered medications. These drugs include iron supplements and antifungal drugs such as itraconazole, ketoconazole, and fluconazole. Cephalosporin antibiotics, such as cephalexin or cefpodoxime, should ideally be given two hours before or after administering famotidine to optimize its absorption. Separating oral administration between other drugs by one hour is generally recommended. Some antacids can diminish the absorption of famotidine.

What is the difference between famotidine (Pepcid) and ranitidine (Zantac)?

Famotidine (Pepcid) and ranitidine (Zantac) are both in the class of drugs called H2 receptor antagonists, which block histamine.

There are some physiologic differences between famotidine and ranitidine that include:

• Famotidine is given one to two times per day and ranitidine is given two to three times per day
• Famotidine is eight to nine times more effective at suppression of gastric acid secretion
• Ranitidine has some effect on gastric motility and hepatic microsomal enzyme systems, while famotidine does not

Is Pepcid AC the same as Pepcid?

Both Pepcid and Pepcid AC are composed of the same active ingredient (famotidine). Pepcid AC refers to the over-the-counter, lower-strength version, while Pepcid often refers to the prescription strength versions.

What is Pepcid Complete?

Pepcid Complete® is a chewable tablet that consists of famotidine combined with an antacid. The antacid component provides faster relief (minutes) for symptoms of heartburn, while the famotidine takes longer (peak effect 2 hours).

When is the best time to give famotidine to my dog?

The best time to give famotidine is in the morning before feeding breakfast.

Can you crush Pepcid and give it to your dog?

Ideally, Pepcid should not be crushed. Many tablets are formulated to be ingested and broken down in the gastrointestinal tract over time. When crushed, more of the medication is absorbed quickly.

If you are having difficulty medicating your dog, a better alternative is to use the oral liquid formulation (liquid famotidine oral powder for suspension supplied at 50 mg/5 ml), which is available at most pharmacies. Check with your veterinarian for a prescription.

As an alternative to crushing pills, a better approach is to hide the pill in a small amount of food, such as canned dog food, chicken, cheese, or peanut butter. If that is not possible, you can open your dog’s mouth and place it near the back. Here are tips on how to give your dog a pill and how to hide a pill in food.

What human medications or over-the-counter (OTC) medications are safe to give my dog?

There are several human OTC medications safe to use in dogs. Here is a list for your reference.

Drug Library for Pets

Want to learn more about safely administering medication to your dog? Check out PetPlace’s Drug Library.