SMZ, also known as SMX, is an abbreviation for the anti-bacterial drug sulfamethoxazole. This drug is also sold under the brand name Gantanol.
Because bacteria have developed a resistance to it, SMZ is often combined with other drugs and used in the treatment of malaria, urinary tract infections, toxoplasmosis and conjunctivitis.
The side effects of SMZ include dizziness, lethargy, loss of appetite, nausea, vomiting and diarrhea.
Because SMZ can interact negatively with other drugs, tell your veterinarian if your dog is currently taking cyclosporine, methenamine or warfarin.
If you don't give all doses, the infection could recur or even get worse. It's important that you give the dog all of the medication that the veterinarian prescribed, even if the dog seems better. This drug can also make your dog's skin more sensitive to sunlight, causing sunburn.
SMZ can cause a disorder called Stevens-Johnson syndrome, which can be fatal. If a dog develops a rash during treatment with the drug, the medication should be discontinued and you should call a veterinarian.