LSD-induced hallucinogen persisting perception disorder treatment with clonidine: an open pilot study

A pilot open study was conducted in order to evaluate the efficacy of cloni dine in the treatment of LSD-induced hallucinogen persisting perception dis order (HPPD). Eight patients fulfilled entrance criteria. All complained of HPPD for at least 3 months and were drug free at least 3 months. They rece ived fixed low doses of clonidine, 0.025 mg, three times a day for 2 months . They were evaluated by the Clinical Global Impression Scale (CGI) and a s elf-report scale on the severity of symptoms (graded 0-5). Patients scored an average of 5.25 (SD = 0.46) on the CGI and 4 on the self-report scale at baseline, indicating marked psychopathology. One patient dropped out at we ek 3 and a second patient dropped out at week 5. Of the six patients remain ing at the end of 2 months, the average CGI score was 2.5 (SD = 0.55) and t he self-report scale score was 2, indicating mild symptomatology. LSD-relat ed flashbacks associated with excessive sympathetic nervous activity may be alleviated with clonidine in some patients. (C) 2000 Lippincott Williams & Wilkins.