Comment on 'Health aspects of cannabis: revisited' (Hollister)

Dr. Leo Hollister's excellent article begins to address the need for better understanding of the effects of cannabis use on health. The last five years in the US have seen an increase in advocacy groups extolling the medicinal utility of cannabis. On 5 November 1996, this culminated in California (proposition 215) joining the list of states permitting the limited use of cannabis for the medicinal treatment of disorders including intractable pain, glaucoma, nausea induced by chemotherapy for cancer or by AZT or Foscavir for the treatment of AIDS, and for spasticity associated with multiple sclerosis (Burstein, 1997; West and Homi, 1996; Grinspoon and Bakalar, 1995; Nahas and Manger, 1995). Of these potential uses for cannabis, the evidence for the treatment of nausea and the stimulation of appetite in cachetic patients appears most promising (for a review see Voth and Schwartz, 1997). Yet not only do doubts remain about the effectiveness of cannabis for the treatment of these conditions, since definitive controlled clinical studies are typically lacking (Voelker, 1997), but there is concern that any therapeutic advantage is more than offset by its harmful effects. Within this context of increased medical sanction for the use of cannabis in specific disease states for which it may have therapeutic potential, evaluating its risks vs. benefits profile is essential to rational prescribing. In addition, evaluating the public health risks associated with reports of increased risks of cannabis use (Robertson et al., Poulton et al., 1997), is of concern to advocates of its widespread legalization, governmental agencies attempting to limit its promulgation, and to planners and providers of health care charged with providing treatment for its consequences.