- SSRIs/SNRIs are toxic to pets
- 1–8 h
- Affects: Nervous system
Why this verdict for cats
Human antidepressants are dangerous to cats and can cause tremors, a racing heart and agitation. Treat ingestion as an emergency.
Warning signs to watch for
- Agitation
- Tremors
- Dilated pupils
⚠ If your cat ate antidepressants
Act immediately — don't wait for symptoms.
- Call your vet or a pet poison helpline right away.
- Note how much was eaten and when.
- Do not induce vomiting unless a professional tells you to.
Antidepressant poisoning has become one of the most common medication calls to pet poison lines, for a simple reason: these tablets are taken daily by millions of people, and a dropped pill is found by a dog before the owner has finished bending down.
How much is safe?
Never give a human antidepressant to a pet unless a veterinarian prescribed that exact drug and dose — some are used in veterinary behavioural medicine, but at species-specific doses that bear little relation to a human tablet. The risk varies widely by drug class and by pet size, and extended-release formulations are more dangerous because the full dose is delivered over hours. Cats are affected at proportionally smaller amounts.
What happens if a cat eats too much?
The main concern is serotonin syndrome — too much serotonin activity at once. It looks like agitation and restlessness, tremors, dilated pupils, a racing heart, vocalising, a high body temperature, vomiting and diarrhoea, and in severe cases seizures. Confusingly, some pets go the opposite way and become heavily sedated and wobbly instead. Signs typically begin within one to four hours, sooner with immediate-release tablets.
⚠ What to do if your cat ate antidepressants
Call a vet or poison line immediately with the drug name, the strength, how many are missing and your pet's weight (ASPCA 888-426-4435 · Pet Poison Helpline 855-764-7661). The drug name genuinely matters — treatment differs between an SSRI, an SNRI and a tricyclic. Bring the packet. Most pets do well with prompt care: decontamination, sedation to control agitation and tremors, temperature control, fluids, and in some cases a specific serotonin blocker.
⚠️ Worried your pet got into this?
Frequently asked questions
My dog is on a behavioural medication already — is a stray extra pill of mine dangerous?
Potentially more so, because the effects can add together. Tell the vet exactly what your pet is already taking.
The pill was a low dose — is that reassuring?
Only relative to weight, and a 'low' human dose is often a high dose for a 6 kg dog. Let the poison line do the arithmetic rather than guessing.
More medications for cats
By the CanMyPet Editorial Team · Reviewed against ASPCA Animal Poison Control, the American Kennel Club (AKC) and Pet Poison Helpline · Last updated July 31, 2026.
Sources
- ASPCA — People Foods to Avoid Feeding Your Pets
- American Kennel Club — Dog Nutrition
- Pet Poison Helpline — Poison List