Pain & fever · cat safety
Are diclofenac, naproxen and Meftal toxic to cats?
Severe
No — period-pain, migraine and joint tablets such as Meftal, Meftal-Spas, Naxdom and Voveran contain NSAID painkillers that cats can't handle. They cause bleeding stomach ulcers and kidney failure, and naproxen stays in the body a long time. Go to a vet now with the strip.
Why severe: Naproxen is 'very poisonous to dogs and cats' with a narrow safety margin (Pet Poison Helpline); every human NSAID can ulcerate a cat's stomach.
- Name
- Diclofenac, naproxen and mefenamic acid tabletsalso Meftal, Meftal-Spas, Naxdom, Voveran, Period-pain and migraine tablets
What counts
Mefenamic acid, naproxen and diclofenac tablets and capsules, and children's mefenamic acid syrups.
What's in it
NSAIDs (non-steroidal anti-inflammatory drugs). They block the prostaglandins that protect the stomach lining and keep blood flowing to the kidneys; cats clear them poorly (Merck).
Brands it hides in
- Meftal and Meftal-Spas (mefenamic acid)
- Naxdom and other naproxen tablets
- Voveran and other diclofenac tablets
- Children's mefenamic acid fever syrups
Symptoms to watch for
- Vomiting, sometimes with blood
- Black, tarry poo
- Not eating, belly pain
- Pale gums, weakness
- Drinking and peeing changes (kidney injury)
- Rarely: facial twitching or seizures
Stomach signs can start within hours; kidney injury may take a few days to show, so vets recheck blood tests (Merck).
What to do — now
Go to a vet now. Take the strip — the vet needs the drug name.
- Don't make your cat vomit at home unless a vet tells you to.
- Never give a cat a human painkiller, even a children's syrup.
Where Indian cats meet it
Period-pain strips in handbags and bedside drawers, migraine tablets, and joint-pain pills for elders — plus well-meaning owners who give a painkiller to a limping cat.
Myth or fact
Myth“Mefenamic acid is mild — it's even given to children”
FactHuman NSAIDs 'can be extremely dangerous to pets' and should never be given without a vet (Pet Poison Helpline). Children's syrups are not cat medicines.
Cat-safe swap: Ask your vet for cat-safe pain relief.
Sources
- Pet Poison Helpline: Naproxen
- Pet Poison Helpline: NSAIDs
- Merck Veterinary Manual: Toxicoses from human analgesics
Facts last checked
General information for cat parents, not a diagnosis or a treatment plan. The facts come from ASPCA, Pet Poison Helpline, International Cat Care, the Merck Veterinary Manual and the other sources listed on every page — and we say so when the evidence comes from dogs or people. If your cat may have eaten something harmful, call your vet.