Is sulfamethoxazole + trimethoprim a penicillin antibiotic?

iatroX medicinesPublished 21 August 2026Reviewed 21 August 2026

The answer

Answer

No. It combines a sulfonamide antibacterial with trimethoprim and does not belong to the penicillin class.

Co-Trimoxazole 80 mg/400 mg Tabletsemc · SmPC Current selected SmPC · Version 12

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sulfamethoxazole + trimethoprim · Medicine question

iatroX medicinesPublished 21 August 2026Reviewed 21 August 2026

The answer

No. It combines a sulfonamide antibacterial with trimethoprim and does not belong to the penicillin class.

Co-Trimoxazole 80 mg/400 mg Tabletsemc · SmPC Current selected SmPC · Version 12

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