But they are the dopes. There is also evidence it can trigger heart attacks. The drug can cause hallucinations, aggravate schizophrenia and other mental disorders and undermine the effects of anti-psychotic treatment. Other effects include infertility and impotence. Excessive use has been linked to low sperm count and, in women, reduced fertility.
Supporters claim the drug relieves pain.
Indeed, the Government is funding trials to see if it can help multiple sclerosis sufferers. But the trials use a special type of cannabis inhaled as a vapour which does not allow the user to get high. As a cannabis smoker inhales, about 400 different chemicals are released into the bloodstream via the lungs. It then rushes straight to the brain. The pulse rate increases, blood pressure goes down, eyes become bloodshot and the mouth dry.