No doubt I have forgotten much pharmacology since I was a student, but one diagram in my textbook has stuck in my mind ever since. It illustrated the natural history, as it were, of the way in which new drugs are received by doctors and the general public. First they are regarded as a panacea; then they are regarded as deadly poison; finally they are regarded as useful in some cases.
It is not easy to say which of these stages the medical use of cannabis and cannabis-derivatives has now reached. The uncertainty was illustrated by the on-line response from readers to an article in the latest New England Journal of Medicine about this usage. Some said that cannabis, or any drug derived from it, was a panacea, others (fewer) that it was deadly poison, and yet others that it was of value in some cases.
The author started his article with what doctors call a clinical vignette, a fictionalized but nonetheless realistic case. A 68-year-old woman with secondaries from her cancer of the breast suffers from nausea due to her chemotherapy and bone pain from the secondaries that is unrelieved by any conventional medication. She asks the doctor whether it is worth trying marijuana since she lives in a state that permits consumption for medical purposes and her family could grow it for her. What should the doctor reply?