Neomycin is an antibiotic that is effective against an unusually wide variety of both gram-positive and gram-negative organisms. Since its isolation in 1949 from a strain of Streptomyces fradiae by Waksman and Lechevalier, it has been the subject of many extended laboratory and clinical studies. Neomycin has been found to be an effective topical agent in the treatment of cutaneous bacterial infections. It has also afforded excellent results in preoperative preparation of the intestine, since there is very little absorption of this antibiotic through the gastrointestinal tract. In addition, it has proved effective in stubborn urinary tract infections treated for short periods of time by the intramuscular route. However, several clinical studies have shown that prolonged parenteral administration of neomycin produces definite ototoxic and nephrotoxic effects; hence, its parenteral use is not generally recommended.
Occasionally, however, a patient with a serious infection due to an organism not sensitive to other