The medical use of Marinol is highly restricted because of the potential side effects. Fortunately, newer, better anti-emetic medications have been developed and are now available. Because of a placebo effect, a patient may believe a drug is helpful when it is not. Anecdotal evidence may point to a drug having medicinal value, but this needs to be followed up with scientific studies. Because of marijuana's addictive and mind-altering effects, a placebo effect can be magnified.
Users are likely to exaggerate the benefits.
For example, there have been numerous reports from patients that have claimed that marijuana has cause improvement in multiple sclerosis. In addition, many reports of marijuana's beneficial effects are based not on science but on anecdotes from individuals who claim results for themselves. While these individuals may feel they have benefited, we cannot base public policy decisions on important issues on anecdotal information. Unfortunately, many in the press and elsewhere do not look beyond such information. The best available science, however, clearly and overwhelmingly demonstrates the contrary.