This is a tricky subject because people should not be tempted into diagnosing cat health problems on their own and then purchasing over the counter pet drugs to treat the illness. However, some drugs not labeled for use by cats can be used to treat specific cat health conditions, which obviously simplifies life. And knowledge used wisely results in better cat caretaking.
WARNING: Please check with your veterinarian before administering drugs to your cat. All drugs are a form of poison and for example pain killers designed to be used by people can kill cats even in relatively small doses. Flea treatments can kill cats too. Extreme care is required when administering drugs to kittens and cats. Below is a chart that shows drugs suitable for cats that can be bought over-the-counter with your vet’s agreement. The drugs referred to are mainly available in North America but some are universal. Substitutes will be available in other countries under a different name but please check.