Penicillin and streptomycin can be used in combination, but should be used under medical supervision. In addition, if it is an injection, it needs to be used in separate vials, and not in the same vial. Penicillin and streptomycin belong to two different types of antibiotics, equal amount of joint use can play a synergistic effect; penicillin dosage is too large, it will affect the activity of streptomycin. Penicillin and streptomycin injectable dosage forms may react when they are compounded in the same vial, which may affect the efficacy of the drug, but may also increase the adverse effects of the drug. Penicillin belongs to the β-lactam antibiotics, the drug mainly inhibits the synthesis of bacterial cell wall, and play a bactericidal effect, on hemolytic streptococcus, Streptococcus pneumoniae, as well as staphylococcus bacteria that do not produce penicillinase have a very good antibacterial effect. Adverse effects of the drug mainly include allergy, renal impairment and so on. Streptomycin belongs to the aminoglycoside antibiotics, the drug is mainly to inhibit the synthesis of bacterial proteins, so as to achieve the effect of sterilization, on the Mycobacterium tuberculosis and the vast majority of gram-negative bacilli have good antibacterial effect. The adverse effects of the drug include nephrotoxicity, ototoxicity and peripheral neuropathy. In order to ensure the safety of the drug, specific cases need to follow the doctor’s instructions.