Science Cannabis

174 THE SCIENCE OF MARIJUANAexposure to cannabis. Nevertheless some depressed patients report greatbenefits from cannabis:In the spring of 1990 I smoked marihuana for the first time since 1973. Tomy amazement, a quarter of a joint changed my self perception to matchthe person others saw. It was like night and day. I had experienced a similarchange only a few times before, when [amitriptyline] kicked in and liftedme out of the depths. But with [amitriptyline] it took four days of rapidlyincreasing doses; with marihuana it took less than five minutes, every time.Since then I have been using marihuana to think clearly, to concentrate,and simply to enjoy the beauty of the world in a way I couldn't for years.(Grinspoon and Bakalar, 1993)In sleep laboratory studies orally administered THC at doses of 10-30 mg has been shown to cause increases in deep slow wave sleep, but atthe same time-as with other hypnotic drugs —there is a decrease indreaming or rapid eye movement (REM) sleep. After repeated treatmentwith large doses of THC there was evidence of some degree of hangoverduring the morning after treatment, and a rebound in the amount ofREM sleep. THC thus does not appear to offer any advantages overexisting sleeping pills, and it has the disadvantage of causing intoxicationprior to sleep.This seems to be another example in which the original case forusing cannabis has been made obsolete by the development of modernantidepressants (e.g., Prozac®), antianxiety agents (e.g., Valium®), andsleeping pills (e.g., temazepam and zopiclone).ConclusionsThere are clearly several possible therapeutic indications for cannabisbasedmedicines, but for most of them evidence for the clinical effectivenessof the drug is woefully inadequate by modern standards. The exampleof the use of cannabinoids in the treatment of sickness associatedwith cancer chemotherapy shows, however, that it is possible to amasssuch evidence provided resources are devoted to such studies, and unambiguousclinical trial designs are used. One of the obvious complications