Dihydrostreptomycin is an antibiotic compound derived from streptomycin by reduction with hydrogen. The primary mechanism of action of the antibiotic dihydrostreptomycin is binding to and modifying the function of the bacterial ribosome, thus leading to decreased and aberrant translation of proteins, in addition it binds mechanosensitive channel of large conductance (MscL) and modifies its conformation, thus allowing the passage of K+ and glutamate out of, and dihydrostreptomycin into, the cell. It has about the same degree of antibacterial activity as streptomycin, but it is less effective against some gram-negative microorganisms. Because it has a higher risk of irreversible deafness, and its effectiveness is no greater that that of streptomycin, dihydrostreptomycin is no longer used clinically. To date dihydrostreptomycin is approved for veterinary use to treat bacterial infections.

Sulfamethazine is a sulfonamide used to treat a variety of bacterial diseases in animals. It inhibits bacterial synthesis of dihydrofolic acid by competing with para-aminobenzoic acid (PABA) for binding to dihydropteroate synthetase (dihydrofolate synthetase).