By Dial A Vet Veterinary Team
Cats share lounge rooms, benches, and investigating noses with whatever humans leave unattended. Marijuana (cannabis) products containing THC can make cats profoundly sedated, wobbly, or agitated. Edibles and concentrated oils are especially dangerous because a small body weight meets a dense dose. Second-hand smoke in a closed flat can also affect sensitive cats. Toxicity is a veterinary issue regardless of how cannabis is regulated where you live.
Key takeaways
- THC exposure can cause dilated pupils, wobbliness, hiding, vocalising, urinary changes, and rarely seizures.
- Edibles, butter, and oils are higher risk than a brief sniff outdoors.
- Call your vet or Animal Poisons Helpline (1300 869 738) with product details.
- Do not induce vomiting with salt or peroxide unless directed.
- Related: dogs and weed, cat poisoning signs, marijuana effects overview.
How cats get exposed
- Licking oils off benches or fur after spills
- Stealing gummies or chocolate edibles (chocolate adds theobromine risk)
- Chewing dried flower or butts
- Grooming residue off their coat after rolling in spilled material
- Enclosed rooms heavy with smoke
Signs
Quiet hiding or paradoxical agitation, dilated pupils, wobbly gait, slow responses, drooling, vomiting, changes in heart rate, hypothermia risk in deeply sedated cats, and rarely tremors or seizures. Cats often mask illness; subtle dullness still warrants a call.
When it is an emergency
Collapse, seizures, severe distress, known concentrate ingestion, or chocolate or xylitol edibles: emergency care with the product label.
Immediate steps
Remove access. Wipe obvious oil from fur with a damp cloth if a clinician agrees that is safe. Estimate amount. Call 1300 869 738 or your clinic. Keep the cat warm, quiet, and away from balconies or stairs. No alcohol, coffee, or leftover human medicines.
Veterinary care
Supportive monitoring, fluids, temperature support, anti-nausea care, and seizure control when needed. Decontamination decisions are case-by-case. Judgement-free history helps, including illegal or prescription medical cannabis products.
Prevention
Latch cannabis storage. Never leave edibles on coffee tables. Ventilate if you smoke and keep cats out of the room. Multi-pet homes need the same rules for dogs and cats; what one species leaves, the other may finish.
Legal note without the lecture
Australian access rules differ by product and state. None of that changes first aid: protect the cat, call professionals, take packaging with you.
Practical notes for Australian homes
Keep the Animal Poisons Helpline number (1300 869 738) in your phone before you need it. After hours emergency clinics fill quickly on weekends and holidays, so call ahead while you travel when advised. Hot weather makes dehydrated, vomiting pets deteriorate faster; use air-conditioned transport when you can and do not delay because the day feels busy.
Write a short card with your pet's weight, usual diet, and any chronic medicines. Hand it to triage nurses so details are not lost in the rush. Ask what home observations matter most in the first 24 hours after discharge.
If cost is a concern, say so early. Teams can often stage diagnostics while still covering the urgent risks. Avoid stacking random over-the-counter human products into the plan; they muddy the picture and can cause harm.
Extra context for worried owners
Write down a timeline while details are fresh: when the exposure happened, what was left on the floor, and which pets share the house. That scrap of notes helps Helpline staff and triage nurses more than a stressed verbal guess. If multiple pets had access, mention every animal, even the ones that "probably" did not eat anything.
Photograph packaging, plants, or broken objects before you bin them. Clear labels beat memory after a sleepless night. If you are driving to an emergency clinic, call ahead so the team can prepare; say whether your pet is vomiting in the car, seizuring, or having trouble breathing.
Do not crowd the pet with loud voices or forced exercise "to keep them awake" unless a clinician asks for that. Quiet transport, a non-slip surface, and a second person to watch breathing are enough for most trips. Keep a portable bowl of water available only if your vet said drinking is still appropriate.
During recovery at home, follow the feeding and recheck plan you were given. Soft stools for a day can be ordinary after gut stress; repeated vomiting, black stools, pale gums, collapse, or new tremors are reasons to call back the same day. Avoid adding new supplements, bone broths from oniony stock, or leftover human medicines while you wait for the all-clear.
Australian summers make dehydration and heat stress stack onto toxin cases. Park in shade, use air-conditioning if you have it, and do not leave animals in cars while you queue for reception. If bushfire smoke or extreme heat is also in the forecast, say so; clinics may adjust monitoring advice.
FAQ
Can cats get "high" from second-hand smoke alone?
Enclosed, poorly ventilated exposure can affect cats. Eating products is usually worse. Call if behaviour changes.
Is medical cannabis prescribed for cats something I should start at home?
Only use medicines prescribed by your own veterinarian for your cat. Do not share human products.
My cat ate a cannabis chocolate. What matters most?
Both THC and chocolate. Say so clearly when you call.
How long can signs last?
Often many hours; some cats need overnight monitoring. Follow clinic advice.
Talk with a vet
Worried about cannabis exposure? Book a Dial A Vet consult.
References
- Merck Veterinary Manual. Toxicosis in dogs and cats from tetrahydrocannabinol (THC).
- ASPCA. Marijuana safety in pets.
- Animal Poisons Helpline (Australia): 1300 869 738
Disclaimer: Educational only. This page does not replace an examination or advice from your own veterinarian. If you are worried about your pet right now, contact your local vet or nearest emergency animal hospital.