 RATIONALE: Drugs used in chemotherapy work in different ways to stop the growth of cancer cells, either by killing the cells or by stopping them from dividing. Chemoprotective drugs, such as alpha-lipoic acid, may protect normal cells from the side effects of chemotherapy. Alpha-lipoic acid may also prevent damage to nerves that carry information to and from the brain and spinal cord to the rest of the body. It is not known whether alpha-lipoic acid is more effective than placebo in preventing peripheral neuropathy. 