Ribostamycin(Vistamycin), a new aminoglycoside antibiotic, developed by MEIJI SEIKA KAISHA LTD., was given intramuscularly to 50 patients with various acute inflammatory diseases in otolaryngologic field : 10 with acute tonsillitis, 8 with acute otitis media, 16 with otofuruncle, 3 with peritonsillar abscess, 3 with nasal furuncle, 4 with acute paranasal sinusitis, and 6 with other diseases including otogenic brain abscess and secondary infection of postoperative cases. The excellent and good (+++ and ++) effect was obtained in 45 of 50 patients, the effectivity rate being 90%. No side effects were observed, especially the symptoms of ototoxicity.