--toxic peripheral neuropathy immediately springs to mind; many of the metal based chemotherapy drugs are nerve toxic, and have a long history of causing neuropathy.

The good news is that over time, some recovery can usually be expected. The bad news it that nerves regenerate more slowly than just about any other body tissue, so improvement is extremely gradual and hard to notice except in long-term retrospect (we're talking months to years).

Come look at our neuropathy forum:

http://neurotalk.psychcentral.com/fo...aysprune=&f=20

Also, here's a good overview of toxic neuropathies:

http://www.neuro.wustl.edu/NEUROMUSC...ther/toxic.htm