Forty consecutive cases of
causalgia treated during a 7-year period are presented. The patients ranged in age between 17 and 55 years, and all patients were males who received their nerve
injuries from missile or shrapnel
wounds. The greater occipital nerve was involved in two cases, median nerve in 10, sciatic nerve in 12, brachial plexus in seven, cauda equina in five, and multiple nerves in four cases. Each patient was treated with
phenoxybenzamine, a postsynaptic alpha 1-blocker and presynaptic alpha 2-blocking agent. The
drug was given orally in gradually increasing increments until a maximum daily dose of 40 to 120 mg was reached.
Duration of treatment was usually 6 to 8 weeks. Total resolution of
pain was achieved in all cases. The follow-up period ranged between 6 months and 6 years. Side effects of
phenoxybenzamine were minimal and transient, consisting primarily of mild
orthostatic hypotension and ejaculatory problems. We conclude that oral
phenoxybenzamine is a simple, safe, and effective treatment of
causalgia.