Antimicrobial potency As an antibiotic,<unk>  is noted to possess effectiveness mainly against Gram-positive organisms. Some Gram-negative organisms such as Neisseria gonorrhoeae and Leptospira weilii are also reported to be susceptible to<unk> .
Benzylpenicillin
Extended-spectrum penicillin
Penicillin
Phenoxymethylpenicillin
Procaine benzylpenicillin
Carbenicillin
Tetracycline
Oxytetracycline