Streptomycin

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Streptomycin, antibiotic agent produced by a filamentous (thready) soil bacterium, Streptomyces griseus. Microorganisms that cause many serious diseases, such as tuberculosis, leprosy, and cholera, are susceptible to streptomycin. The first drug effective against tuberculosis, it is still used for this condition, although it has been replaced for most purposes by newer, more effective antibiotics of the same chemical family, the aminoglycosides. These include gentamicin, tobramycin, amikacin, and kanamycin.

An important drawback to the use of streptomycin is the development of resistance to the drug by certain bacteria. Resistance may be delayed by supplementing streptomycin with para-aminosalicylic acid or isoniazid. Streptomycin occasionally causes damage to the vestibular or auditory division of the eighth cranial nerve. Aminoglycosides may also damage the kidney.

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