BMA Report Calls for Change in Law and Development of New Cannabis-based Medicines

The British Medical Association today (Tuesday 18 November) publishes a major report on the therapeutic uses of cannabis. Therapeutic Uses of Cannabis draws a distinction between recreational misuse and using the drug to relieve pain. The report acknowledges that thousands of people resort to taking cannabis illegally in an attempt to ease their distressing symptoms, for example, glaucoma, muscle spasms, chronic pain and nausea.

The report includes moving accounts from individual patients who have used cannabis in desperation when conventional drugs have failed them. However because of the current state of the law, much of the evidence from those claiming relief is anecdotal.

The BMA report Therapeutic Uses of Cannabis examines the scientific evidence for the wider medicinal use of cannabinoids ~ derivatives of cannabis ~ for a range of medical problems: nausea and vomiting associated with cancer chemotherapy muscle spasticity pain anorexia epilepsy glaucoma bronchial asthma mood disorders and psychiatric conditions hypertension.

The report underpins the policy of the BMA that certain additional cannabinoids should be legalised for wider medicinal use. It sets the research agenda and identifies the legal steps that need to be taken before new treatments can be developed.

However the report also warns that cannabis contains more than 400 chemical compounds, (including more than 60 cannabinoids) some of which are potentially harmful to health.

It has been estimated that smoking a cannabis cigarette (containing only herbal cannabis) leads to three times greater tar inhalation than smoking a tobacco cigarette. The levels of tar retained in the respiratory tract are also three times higher. Chronic cannabis smoking, like tobacco smoking, therefore increases the risk of cardiovascular disease, bronchitis, emphysema and probably carcinomas of the lung. Adverse effects of chronic use include suppression of ovulation in women, decreased sperm count in men, sedation and anxiety.

Street and illicit cannabis can also contain adulterants, including pesticides, as well as naturally occurring contaminants such as microbes and fungi which can pose a risk to immuno-suppressed patients such as people with AIDS.

Because cannabis contains so many different cannabinoids in varying combinations, simply smoking or eating the drug will not tell us which agents are beneficial.

The report therefore recommends further research including investigating the long term effects of cannabinoids on chronic conditions. To facilitate research, the BMA recommends a change in the law. It suggests that advice should be given from the World Health Organisation (WHO) to the United Nations Commission on Narcotic Drugs to reschedule certain cannabinoids under the United Nations Convention on Psychotropic Substances. The Home Office could then amend the Misuse of Drugs Act in response. If WHO feels unable to give such advice, the Government should consider changing the Misuse of Drugs Act to allow cannabinoids to be prescribed to patients with particular medical conditions whose symptoms are being inadequately controlled under present arrangements. A central registry should be kept of those patients to allow follow up of long term effects.

Therapeutic Uses of Cannabis is published for the BMA by Harwood Academic Publishers @ =A311.99 paperback (ISBN 90-5702-318-0) and =A323.00 cloth (ISBN 90-5702-317-2).