Loperamide
Also known as: Imodium, Imodium A-D, Neo-Diaral, K-Pek II, Diah-Limit, Diarolaeze, Entrocalm, Norimode
Loperamide is a medication used to help control diarrhea in pets. * **Breed Warning:** Do NOT use this medication in herding breeds (such as Collies, Shelties, Australian Shepherds, or mixed breeds with white feet) unless they have been specifically tested and cleared for the MDR1 gene mutation. In these dogs, loperamide can cause severe and life-threatening neurological reactions. * **Cats:** Use in cats is generally not recommended unless strictly directed by your veterinarian, as it can cause unusual excitatory behavior. * **Administration:** Liquid forms are often preferred for small dogs to ensure accurate dosing. Do not dilute the oral liquid with other liquids. * **When to call the vet:** Contact your veterinarian immediately if the diarrhea persists for more than 48 hours, if your pet appears unusually listless, depressed, or uncoordinated, or if they develop a high fever or bloody stool.
Dosage must be set by your veterinarian for your specific pet. Never give human medication or another pet’s prescription without veterinary guidance.
What it is used for
- Diarrhea
- Diarrhea
- Management of non-specific acute and chronic diarrhoea, and irritable bowel syndrome
- Antidiarrheal (Rabbits)
- Antidiarrheal (Mice, Rats, Gerbils, Hamsters, Guinea pigs, Chinchillas)
- Antidiarrheal
- Antidiarrheal
- Antidiarrheal
- Adjunctive treatment for diarrhea associated with chemotherapy
- Antidiarrheal
- Antidiarrheal
- Management of non-specific acute and chronic diarrhoea, and irritable bowel syndrome
How it is given
Possible side effects
- Constipation
- Bloat
- Sedation
- Paralytic ileus
- Toxic megacolon
- Pancreatitis
- CNS depression (especially in MDR1-mutant dogs)
- Excitatory behavior (cats)
- Excitability (especially in cats)
- Profound sedation and ataxia (in MDR1 mutant dogs)
Cautions & contraindications
- Dogs tested positive for the ABCB1-1Δ (MDR1) mutation
- Untested dogs of herding breeds susceptible to the MDR1 mutation
- Diarrhea caused by toxic ingestion (until the toxin is eliminated)
- Known hypersensitivity to narcotic analgesics
- Infectious enteritis (relative contraindication, as decreased motility can delay pathogen clearance)
- Intestinal obstruction
- Dogs likely to be ivermectin-sensitive (MDR1/ABCB1 mutation, e.g., Collies, Australian Shepherds)
- Infectious enteritis (where decreased motility may delay pathogen clearance)
- Toxigenic diarrhea
- Use with caution in patients with **hypothyroidism, severe renal insufficiency, adrenocortical insufficiency (Addison's disease)**, and in geriatric or severely debilitated patients. Use with extreme caution in patients with **head injuries or increased intracranial pressure**, as well as acute abdominal conditions (e.g., colic), as opiates may obscure the diagnosis or clinical course. Use with extreme caution in patients suffering from **respiratory disease** or acute respiratory dysfunction (e.g., pulmonary edema secondary to smoke inhalation). Use with extreme caution in patients with **hepatic disease** exhibiting CNS clinical signs of hepatic encephalopathy, as hepatic coma may result. **Small Patient Dosing:** Many clinicians recommend avoiding tablet/capsule forms in dogs weighing less than 10 kg due to potency; dosage titration using liquid forms is recommended for safe use.
Drug interactions
- Amiodarone: Inhibits P-glycoprotein (P-gp), which may increase loperamide plasma concentrations and risk of CNS toxicity.
- Carvedilol: Inhibits P-glycoprotein (P-gp), which may increase loperamide plasma concentrations and risk of CNS toxicity.
- Erythromycin: Inhibits P-glycoprotein (P-gp), which may increase loperamide plasma concentrations and risk of CNS toxicity.
- Ketoconazole: Inhibits P-glycoprotein (P-gp), which may increase loperamide plasma concentrations and risk of CNS toxicity.
- Itraconazole: Inhibits P-glycoprotein (P-gp), which may increase loperamide plasma concentrations and risk of CNS toxicity.
- Quinidine: Inhibits P-glycoprotein (P-gp), which may increase loperamide plasma concentrations and risk of CNS toxicity.
- Tamoxifen: Inhibits P-glycoprotein (P-gp), which may increase loperamide plasma concentrations and risk of CNS toxicity.
- Verapamil: Inhibits P-glycoprotein (P-gp), which may increase loperamide plasma concentrations and risk of CNS toxicity.
- Other antimotility drugs: Additive reduction in GI motility, increasing risk of ileus
Frequently asked questions
What is Loperamide used for in pets?
Loperamide is a medication used to help control diarrhea in pets. * **Breed Warning:** Do NOT use this medication in herding breeds (such as Collies, Shelties, Australian Shepherds, or mixed breeds with white feet) unless they have been specifically tested and cleared for the MDR1 gene mutation. In these dogs, loperamide can cause severe and life-threatening neurological reactions. * **Cats:** Use in cats is generally not recommended unless strictly directed by your veterinarian, as it can cause unusual excitatory behavior. * **Administration:** Liquid forms are often preferred for small dogs to ensure accurate dosing. Do not dilute the oral liquid with other liquids. * **When to call the vet:** Contact your veterinarian immediately if the diarrhea persists for more than 48 hours, if your pet appears unusually listless, depressed, or uncoordinated, or if they develop a high fever or bloody stool.
Is Loperamide safe for my pet?
Dosage must be set by your veterinarian for your specific pet. Never give human medication or another pet’s prescription without veterinary guidance.
This article is for general education and is not a substitute for professional veterinary advice. If your pet is unwell, please consult a veterinarian.
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