PSYCHOSIS LINK NOT UNDERSTOOD

Trevor Turner is a very experienced and highly respected psychiatrist
but he's being a bit disingenuous when he writes that he has never
seen "a psychosis due to cannabis" (letter, 20 December). There is a
great deal of research which points to a connection between the
emergence of psychosis and use of cannabis, but the exact relationship
between them remains very unclear.

What is clear from my longer but much less distinguished career in the
same field is that there are some people with a susceptibility, for
whatever reason, to mental illness who should stay well away from
cannabis - and other street drugs, for that matter. They are no
different from those, myself included, who should keep away from
alcohol, or others, with different vulnerabilities, who should avoid
salty or fatty foods.

And this, surely, is the point. Drugs are just like anything else we
consume. In moderation, they can be and are safely enjoyed by the
majority of people who use them, but for a minority they pose a
serious risk to their wellbeing and health. Normalising them through
state regulation and taxation of their distribution and consumption
has to be better, especially in the current economic climate, than the
vast waste of public funds in the criminal justice system which is a
direct result of their continuing demonisation.

Jeremy Walker, London WC1