Should doctors prescribe cannabinoids?

The medical use of cannabis was advocated in the United States in the 1970s and 1980s when clinical trials of oral synthetic tetrahydrocannabinol (THC) and other oral synthetic cannabinoids reported efficacy in controlling nausea in patients with cancer who were undergoing chemotherapy.1 Dronabinol (an oral synthetic THC) was approved by the Food and Drug Administration in 1985 for this indication,1 but it was not widely used because patients were unable to titrate doses or disliked its psychoactive effects.1 It is still available in the US, United Kingdom, and the rest of Europe. Box 1 outlines the different formulations of cannabinoids, the term we use for the sake of clarity and convenience to refer to synthetic cannabinoids and drugs derived from the cannabis plant, such as nabiximols. Box 2 lists indications for which cannabinoids have been approved for medical use. In the US, the smoking of cannabis has been advocated for medicinal purposes.1 Since 1996, 20 US states and the District of Columbia have legislated (11 after citizen initiated referendums) to allow the medical use of cannabis, often to treat a much broader range of indications than those approved by the FDA or other regulators (see box 2).2 In California, for example, doctors can recommend cannabis for any medical use if they believe that the patient may benefit.2 These laws have created clinical conundrums for doctors in these US states.3 In the UK a cannabis based medical extract, nabiximols (see box 1)4 has been approved for ?symptom improvement in patients with moderate to severe spasticity due to multiple sclerosis who have not responded adequately to other anti-spasticity medication and who demonstrate clinically significant improvement in spasticity related symptoms during an initial trial of therapy.on a named patient basis.?5 Should doctors consider prescribing cannabinoids for this indication? Should they consider prescribing nabiximols off label for other chronic conditions? What should doctors do if their patients disclose that they are smoking cannabis for medical purposes?