Development of polyneuropathy during thalidomide therapy.

Seven patients with prurigo nodularis and one with aphthous stomatitis were given 40-115 g of thalidomide for 1 to 6 years. They all developed a predominantly sensory peripheral neuropathy mainly involving the lower limbs. Five patients had an unpleasant tight feeling around the feet. Nerve conduction studies showed small sensory action potentials from the lower limbs with normal or only mild slowing of sensory conduction velocity indicating an axonal neuropathy. The dermatological disorder improved dramatically in all, but treatment had to be discontinued because of the severe side-effects. Thalidomide, if used, should be given only over a short period because of its neurotoxic effect.