What are the side effects of septra (sulfamethoxazole and trimethoprim)?. i have a uti and thats the antibiotic they gave me. so yeah what are they?. they also gave me pyridium.

Septra (sulfamethoxazole and trimethoprim): This is a brand name for a sulfonamide antibiotic combined with trimethoprim (another active agent). The major side-effects are allergic reactions and these can take numerous forms. Pyridium (phenazopyridine) is an agent to manage the pain on urination until the antibiotic takes effect. Hope you are better soon.