amoxicillin + sulfamethoxazole + trimethoprim

This is a combination of three antibiotics—amoxicillin, sulfamethoxazole, and trimethoprim. Amoxicillin is a penicillin-type beta-lactam antibiotic that inhibits bacterial cell wall synthesis. Sulfamethoxazole is a sulfonamide antibiotic that inhibits dihydropteroate synthase, interfering with folic acid synthesis in bacteria. Trimethoprim inhibits bacterial dihydrofolate reductase, blocking another step in folic acid production. The combination of sulfamethoxazole and trimethoprim (often known as co-trimoxazole) acts synergistically to inhibit sequential steps in the bacterial folic acid pathway, resulting in bactericidal activity[3][6][8]. Amoxicillin works via a different mechanism targeting cell wall synthesis[1][3]. This triple combination would theoretically provide broad-spectrum antibacterial coverage by combining two mechanisms—cell wall inhibition and dual blockade of folate metabolism.