Classification: medicamenta antibacterial in duo genera dividuntur: antibiotica et medicamenta antibacteria synthetica. Antibiotici sic dicti sunt metabolitae a microorganismis producti;  quae incrementum vel nonnullos microorganismos inhibere possunt.  Sic dicta medicamenta synthetica antibacteria sunt substantiae antibacteriales ab hominibus productae per synthesim chemicam, non per metabolismum microbialem.

Antibiotica: Antibiotica plerumque in octo genera dividuntur: 1. Penicillins: penicillinum, ampicillinum, amoxicillinum, etc.; 2. Cephalosporins (pioneermycins): cephalexin, cefadroxil, ceftiofur, cephalosporins, etc.; 3. Aminoglycosides: streptomycin, gentamicin, amikacin, neomycin, apramycin, etc.; 4. Macrolides: erythromycin, roxithromycin, tylosin, etc.; 5. Tetracyclina: oxytetracyclinum, doxycyclinum, aureomycin, tetracyclinum, etc.; 6. Chloramphenicol: florfenicol, thiamphenicol, etc.; 7. Lincomycins: lincomycin, clindamycin, etc.; 8. Alia genera: colistin sulphate, etc.