Loperamide (Imodium®) for Dogs and Cats

Overview of Loperamide (Imodium®) for Canines and Felines

• Loperamide, commonly known as Imodium®, is used to treat diarrhea in cats and dogs.
• Loperamide is a synthetic piperidine derivative, a weak narcotic with antidiarrheal properties.
• Loperamide works by slowing the movement of the intestines. It may decrease intestinal secretions and enhance mucosal absorption.
• The medication is absorbed from the gastrointestinal tract and metabolized by the liver.
• Some veterinarians feel that loperamide has a faster onset of action and longer duration of action than diphenoxylate (Lomotil®).
• Loperamide is available without a prescription but should not be administered unless under the supervision and guidance of a veterinarian.
• This drug is not approved for use in animals by the Food and Drug Administration, but it is prescribed legally by veterinarians as an extra-label drug.

Brand Names or Other Names of Loperamide

• This drug is registered for use in humans only.
• Human formulations: Imodium A-D® (McNeil-CPC), Pepto Diarrhea Control® (Procter and Gamble), and Kaopectate II Caplets® (Upjohn). Loperamide is supplied by numerous drug companies with a variety of trade names and various generic formulations.
• Veterinary formulations: None

Uses of Loperamide for Dogs and Cats

Loperamide is most commonly used to manage acute or sudden-onset diarrhea in dogs and, in some cases, cats. It may also be used for chronic diarrhea under veterinary supervision, especially when linked to inflammatory bowel disease or stress-related gastrointestinal upset.

Pet owners should never use Imodium as a first-line treatment without guidance, as underlying causes like parasites, toxins, or infections must be ruled out first. While it can help reduce symptoms, it does not cure the root cause of diarrhea. Always monitor your pet for signs of improvement or worsening symptoms and consult your veterinarian if the diarrhea persists.

Is Imodium Safe for Dogs and Cats?: Precautions and Side Effects

• While generally safe and effective when prescribed by a veterinarian, loperamide can cause side effects in some animals.
• Loperamide should not be used in animals with known hypersensitivity or allergy to the drug.
• Use with caution in patients with hypothyroidism, kidney disease, Addison’s disease, elderly patients, or severely debilitated animals.
• Loperamide should be avoided in patients with diarrhea caused by toxin ingestion until the toxin is eliminated from the gastrointestinal tract.
• The drug should also be avoided if diarrhea is caused by bacteria.
• Use loperamide with caution in animals with head injuries, lung disease, acute abdominal pain, or liver disease with associated neurologic abnormalities.
• Due to the potential for overdose, animals under 20 pounds (10 kg) should be given loperamide liquid, not tablets.
• Loperamide may interact with other medications. Consult with your veterinarian to determine if other drugs your pet is receiving could interact with loperamide. Such drugs include certain antihistamines, barbiturates, tranquilizers, and monoamine oxidase inhibitors.
• Adverse effects associated with loperamide include constipation, bloating, and sedation.
• The use of loperamide in cats is controversial. Cats may react with excitatory behavior after receiving loperamide.
• Overdose of loperamide might result in nervous system stimulation or depression and respiratory distress.

How Loperamide Is Supplied

• Loperamide is available in 1mg/5ml and 1 mg/ml oral liquid.
• Loperamide is also available as 2 mg capsules and tablets.

Imodium Dosage for Dogs and Cats

• Medication should never be administered without first consulting your veterinarian. If you're concerned about costs related to medication, pet insurance may be able to help. Click here to learn more.
• Loperamide is dosed at 0.04 mg per pound (0.08 mg/kg) three to four times daily.
• Loperamide is also dosed at 1 capsule (2 mg) per 50 pounds (25 kg) if over 20 pounds (10 kg).
• Animals under 20 pounds (10 kg) should only receive the liquid form due to potential for overdose.
• The duration of administration depends on the condition being treated, response to the medication, and the development of any adverse effects.
• Be certain to complete the prescription unless specifically directed by your veterinarian. Even if your pet feels better, the entire treatment plan should be completed to prevent relapse or the development of resistance.