The occurrence of undesirable reactions following lumbar puncture is not uncommon. The incidence has been variously reported as ranging between 5 and 75%.1A prominent feature of the postlumbar puncture reaction, and often its only manifestation, is headache. This symptom usually appears 12 to 24 hours after the puncture, though it may occur in a few hours or may be delayed for several days. Characteristically, the headache is relieved when the patient lies down and becomes accentuated when the patient either sits or stands. In most cases the headache persists for several days, but occasionally it may last for as long as eight weeks. Various explanations have been given for the appearance of the headache, and various factors have been noted that will modify or prevent it. Some observers have felt that postlumbar puncture headache is psychogenic2and that its incidence is greater in persons known to be neurotic.3Other investigators, dealing primarily with psychiatric patients, have stated that the incidence of