Diphenoxylate and Atropine
Also known as: Lomotil, Logen, Lonox, Lomanate, co-phenotrope
### Important Information for Pet Owners * **Purpose**: This medication is used to treat diarrhea or to suppress a chronic, hacking cough in dogs. * **When to Call the Vet**: Contact your veterinarian immediately if the diarrhea persists for more than 48 hours, if your pet becomes extremely lethargic/listless, develops a high fever, or shows signs of abdominal pain. * **Watch for Constipation**: Because this drug slows down the gut, it can cause constipation, especially when used long-term for coughing. Let your vet know if your pet is straining to defecate; a stool softener may be needed. * **Dosing Accuracy**: If you have a small dog and are using the liquid form, measure the dose *very carefully*. Overdosing can cause serious side effects, including severe drowsiness and breathing problems. * **Storage**: Keep this medication strictly out of reach of children and other pets. It is a controlled substance.
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
- As an antidiarrheal
- As an antidiarrheal
- As an antidiarrheal
- As an antidiarrheal
- As an antidiarrheal
- As an antitussive
- As an antitussive
How it is given
Possible side effects
- Constipation
- Bloat
- Sedation
- Paralytic ileus (potential)
- Toxic megacolon (potential)
- Pancreatitis (potential)
- CNS depression or excitation
- Excitatory behavior (especially in cats)
Cautions & contraindications
- Known hypersensitivity to narcotic analgesics
- Patients receiving monoamine oxidase inhibitors (MAOIs)
- Diarrhea caused by toxic ingestion (until the toxin is eliminated from the GI tract)
- Intestinal obstruction
- Bacterial-induced acute diarrhea (may enhance bacterial proliferation)
- Use with caution in patients with **respiratory disease**, **hepatic encephalopathy** (hepatic coma may result), **hypothyroidism**, **severe renal insufficiency**, **adrenocortical insufficiency (Addison's disease)**, **head injuries or increased intracranial pressure**, **acute abdominal conditions** (may obscure diagnosis), and in **geriatric or severely debilitated patients**. * **Small Dogs**: Extreme care is required when dosing dogs under 10 kg; liquid formulations are recommended for accurate titration. * **Cats**: Use is controversial and generally not recommended due to potential excitatory behavior. * **Horses/Infectious Diarrhea**: Opiates may have a detrimental effect in acute diarrhea by enhancing bacterial proliferation, delaying microbe clearance, and prolonging the febrile state. * **Nursing/Pregnancy**: Category C. Excreted in maternal milk; use caution in nursing patients.
Drug interactions
- CNS Depressant Drugs (anesthetics, antihistamines, phenothiazines, barbiturates, tranquilizers, alcohol): May cause increased CNS or respiratory depression when used concurrently.
- Monoamine Oxidase Inhibitors (MAOIs) (e.g., amitraz, selegiline): Contraindicated. Do not use opiate antidiarrheals for at least 14 days after receiving MAOIs due to risk of severe adverse reactions.
Frequently asked questions
What is Diphenoxylate and Atropine used for in pets?
### Important Information for Pet Owners * **Purpose**: This medication is used to treat diarrhea or to suppress a chronic, hacking cough in dogs. * **When to Call the Vet**: Contact your veterinarian immediately if the diarrhea persists for more than 48 hours, if your pet becomes extremely lethargic/listless, develops a high fever, or shows signs of abdominal pain. * **Watch for Constipation**: Because this drug slows down the gut, it can cause constipation, especially when used long-term for coughing. Let your vet know if your pet is straining to defecate; a stool softener may be needed. * **Dosing Accuracy**: If you have a small dog and are using the liquid form, measure the dose *very carefully*. Overdosing can cause serious side effects, including severe drowsiness and breathing problems. * **Storage**: Keep this medication strictly out of reach of children and other pets. It is a controlled substance.
Is Diphenoxylate and Atropine 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.
Worried about your pet?
Peqaboo’s AI helps you track symptoms, understand lab reports, and know when to see a vet.
Get the Peqaboo app