Streptomycin may cause severe toxic nerve reactions. The risk is increased in patients with kidney problems. Other severe problems like vision problems, trouble keeping your balance, certain brain problems, and hearing problems (eg, permanent hearing loss) may also happen. The risk of hearing problems may be increased if you have kidney problems or already have hearing problems. It may be increased if you get high doses of streptomycin, or if you get it for a long time. The risk may also be increased in older people, infants, or people who are dehydrated. If you already have kidney problems or hearing problems, tell your doctor. Your doctor will monitor your progress to lower the possibility of these effects. Your doctor may also run certain tests (eg, hearing and/or kidney tests). Discuss any questions or concerns with your doctor.