London (dpa) - The use of cannabis can unleash a host of serious illnesses and make existing ones worse, according to scientists in Britain.

Regular cannabis use has led to acute psychological problems in a high proportion of people, said Dr Andrew Johns of the Institute of Psychiatry in London.

One study found that 15 per cent of cannabis users identified psychotic symptoms such as hearing voices or irrational feelings of persecution. Cannabis was also associated with high rates of other forms of mental illness such as major depression and adjustment disorder.

The drug seemed to worsen the condition of people already suffering from schizophrenia and heavy use could introduce a state resembling acute schizophrenia with users experiencing more and earlier psychotic relapses.

A review by Professor Heather Ashton of the University of Newcastle published in the British Journal of Psychiatry, said cannabis affected almost every bodily system.

These included heart causing problems that might be serious for people with pre-existing cardiac disease and suppression of the immune system. Smoking between three and four reefers of cannabis produced the same risk of bronchitis and emphysema as 20 or more cigarettes a day.

According to Dr Philip Robson who was also writing in the journal, cannabis is not all bad. The first reports of cannabis being used as a medicine appeared in China nearly 5,000 years ago when it was recommended for malaria, rheumatic pains and childbirth, as was mixed with wine as surgical anaesthetic.

Modern science has shown that chemicals in cannabis can have a therapeutic effect in nausea caused by anti-cancer drugs, multiple sclerosis, loss of appetite, pain, glaucoma, insomnia, anxiety and depression, epilepsy and asthma.

From Sohu.com