Trimethoprim/sulfamethoxazole (TMP/SMX), also known as co-trimoxazole among other names Common side effects include nausea, vomiting, rash, and diarrhea. .. Septrin (Spain); Sulfatrim; Trisul; Vactrim (manufactured and distributed in Laos) . Ciprofloxacin or trimethoprim-sulfamethoxazole as initial...