Science Cannabis

Medical Uses of Marijuana—Fact or Fantasy 137These principles of clinical trial design, although they may appearto be simply common sense, are relatively new. It is only in the past 40years that the concept of the controlled clinical trial has become generallyaccepted. It can be applied not only to the testing of new medicines,but also to the effectiveness of any new medical procedure — althoughthere continues to be resistance to the concept of evidence-based medicineamong some members of the medical profession.The reasons for insisting on these elaborate scientifically controlledtrials was the growing realization that the expectations of both doctor andpatient can influence the outcome of a clinical trial, even though neithermay be consciously aware of this. The importance of the placebo effectmeans that this has to be built into the design of the trials. Not all humanillnesses will show the same degree of susceptibility to the placeboeffect, such treatment is most likely to affect the outcome of conditionsin which there are strong psychological or psychosomatic components,and less likely to influence the outcome of infectious diseases or cancer.Placebo effects are particularly prominent in the treatment of such psychiatricconditions as anxiety and depression, and are often seen in illnessesin which the patient has failed to gain any benefit from existingconventional medicines. Such patients are often desperately seeking newtreatments, which they want to work.There is a real possibility that some of the medical benefits claimedby patients who are self-medicating with cannabis could lie in that category.The patients are usually those for whom conventional medicine hasfailed and they are turning to alternative medicine for relief from theirsymptoms. Cannabis has the added attraction to many of being a naturaland herbal remedy, embedded in centuries of folklore and folk medicine.At the moment hardly any of the medical indications for which herbalcannabis is illegally used can be substantiated by data from scientificallycontrolled clinical trials. The thousands of patients who are currentlyself-medicating rely almost entirely on word of mouth anecdotal evidenceand their own personal experiences of the drug. Anecdotal evidence,however, is not reliable and cannot be used to persuade regulatoryagencies to approve cannabis as a medicine. To the nonscientist thisis hard to understand. The often moving personal accounts of individuals