[Alcohol and the peripheral nervous system]

The most frequent consequence of chronic alcohol intake is a toxic polyneuropathy. It results from inadequate nutrition, mainly deficiency of thiamine and other B vitamins. Additionally there is a direct neurotoxic effect of ethanol. Signs and symptoms are 1. distal sensory disturbances with pain, paresthesia, and numbness in a glove and stockings-pattern, 2. weakness and atrophy of distal muscles, pronounced in the lower limbs, 3. loss of tendon jerks, 4. affection of autonomic fibers. Therapy consists in absolute alcohol abstinence, high-caloric nutrition, parenteral thiamine and other vitamins. Against paresthesia and pain, carbamazepine, salicylates, amitryptiline are effective. Parenteral tioctacid may be tried. The prognosis of alcoholic polyneuropathy is favorable, with alcohol abstinence, within several months up to a few years. In chronic alcoholic patients peripheral nerves frequently are injured by compression during alcohol intoxication. Peroneal nerve lesions result from compression in the region of the neck of the fibula during a prolonged lying position, the radial nerve is injured during sitting with the upper arm placed on the backrest of a bench. Usually pressure palsies resolve spontaneously. Rhabdomyolysis is a rare but life-threatening complication of alcoholic delirium. Symptoms are severe muscle pain, swelling of extremities, pigmenturia. The major complications of rhabdomyolysis are renal and respiratory failure, and cardiac arrhythmias due to electrolyte imbalance. Intensive care is needed with control of hyperkalemia, hydration, alkalinization of urine, hemodialysis if indicated.