Dextromethorphan and Pets

Dextromethorphan, commonly known as DXM and found in products such as Robitussin DM, is an over-the-counter cough suppressant used in many human cold and flu remedies. While veterinarians may rarely use it in very specific circumstances, accidental ingestion or unsupervised dosing in dogs and cats can cause serious central nervous system effects. Never give your pet any human cough, cold, or flu medication without explicit veterinary guidance.

Pets are most often exposed by chewing into bottles, licking spilled syrups, or being given medication intended for people. Many combination cold and flu products also contain additional dangerous ingredients, such as acetaminophen, pseudoephedrine, or antihistamines, which can worsen toxicity or cause separate life-threatening problems. Even plain dextromethorphan can be harmful, especially in small animals, cats, or pets with underlying health conditions.

Signs of dextromethorphan poisoning in dogs and cats may include sedation, agitation, loss of coordination (ataxia), dilated pupils, vomiting, tremors, or seizures. Symptoms can appear within 30 minutes to several hours after ingestion and may progress depending on the dose and product formulation. Because effects are unpredictable and combination products raise the risk of multi-drug toxicity, all suspected exposures should be treated as potentially serious.

To prevent poisoning, store all human medications in a secure location out of reach, clean up spills immediately, and never assume a medication safe for people is safe for pets. If your pet may have ingested dextromethorphan, contact your veterinarian or a pet poison control center right away and have the product label available.