Healthy interest in pure medicinal uses for pot plant

CANNABIS has been used for medicinal purposes since at least 2000 BC. Aside from its psychoactive properties (including euphoria, relaxation and altered perception) it has treated a multitude of ailments including headache, insomnia, fever, water retention, vomiting and pain. More recently its proposed use in multiple sclerosis, Aids-associated wasting syndrome, glaucoma and mental health problems have provoked further debate.

The recent re-upgrading of the drug to class B by Home Secretary Jacqui Smith comes amid concerns about its long-term health effects. Gordon Brown supports this stance, previously claiming the drug was "damaging to society and socially unacceptable...