The Evidence for Medical Use

Practising Consultant of Neurology, Professor Mike Barnes completed an analysis of the 20000 best and highest quality medical and scientific research and trial publications and has graded the efficacy of cannabis against a number of conditions

Professor Barnes' study (which can be downloaded here) found:

Good evidence for chronic pain, including neuropathic pain; spasticity; nausea and vomiting (especially from chemotherapy) and in the management of anxiety.

Moderate evidence for sleep disorders; appetite stimulation; fibromyalgia; post-traumatic stress disorder; and for some symptoms of Parkinson’s disease

Some evidence for the management of agitation in dementia; epilepsy; bladder dysfunction; glaucoma; and Tourette’s syndrome.

There is a theoretical basis and anecdotal evidence, but so far no qualifying evidence of efficacy; for management of dystonia; Huntington’s disease; headache; brain protection in traumatic brain injury; depression; obsessive compulsive disorder; gastrointestinal disorders; psychosis (CBD); and a role in cancer/tumour control.

UPDATE AUG 2018: Check out his latest article written for the British Medical Journal - The Case for Medical Cannabis