Can sulfamethoxazole (bactrim (sulfamethoxazole and trimethoprim) ds) make your acne worse before it gets better?

Yes: I'd check with my physician first, though, since Bactrim (sulfamethoxazole and trimethoprim) itself is famous for producing a different kind of rash that can be dangerous.

No: But it takes 2 or 3 months to determine response. During this time the acne will fluctuate according to factors unrelated to bactrim. This is a med used for bacterial infections. While small doses can be useful for acne, it is not first line. Most adult women with acne will get a poor result. Also it may cause damage to normal bacteria. SPIRONOLACTONE is far more effective and far safer.