The number of people needing medical treatment as a result of cannabis use has risen by roughly half since the Government’s decision to downgrade the drug four years ago, figures have shown.

Since cannabis was changed from a Class B to a Class C drug in 2004, the equivalent of nearly 500 adults and children have been treated every week for its effects.

The Times reported this week that the decision is set to be reversed, with cannabis likely to revert to Class B status after an official review this spring.

David Blunkett, the former Home Secretary, downgraded cannabis in January 2004, making possession a nonarrestable offence in most cases.

Since then, more than 16,500 adults a year have attended hospital citing health problems caused by cannabis, hospital statistics show. In addition, the number of children needing medical attention after smoking the drug has risen to more than 9,200.

Drug campaigners said that the latest figures showed that the downgrading decision was badly mistaken and had sent out the wrong signals about cannabis being a “soft” drug.

Gordon Brown and Jacqui Smith, the Home Secretary, are understood to be determined to return the drug to Class B after the Advisory Council on the Misuse of Drugs reports in the next few months. The independent review into the reclassification of cannabis was prompted by growing concern about the increasing prevalence of new high-strength “skunk” forms, which can be twice as potent as untreated cannabis resin.

Doctors say that cannabis abuse contributes to mental health problems including forms of psychosis, paranoia and schizophrenia. There can be harmful physical side-effects, disrupting blood pressure and exacerbating heart and circulation disorders.

James Clappison, a Conservative member of the Commons Home Affairs Committee, said: “The reclassification of cannabis sent the wrong message and was clearly the wrong decision. These figures show the evident dangers of cannabis abuse and support the case for the drug being restored to Category B.”

The health authority figures show that 16,685 adults were treated by English hospital trusts after abusing cannabis in 2006-07. The previous year it was 14,828 - up from 11,057 in 2004-05. However, this is against a background of rising hospital admissions for all causes of illness.

The Department of Health said that the rising number of treatments reflects improvements in drug treatment and not rising cannabis use. In total, 25,944 people were treated for cannabis use last year.

Class C drug possession carries a maximum two-year prison sentence, with 14 years for supplying the drug, but most offences of cannabis possession by adults now result in a police warning given on the spot, and confiscation of the drug. In the case of Class B drugs, possession carries a five-year sentence, with 14 years for supply.

Advocates of downgrading or legalising cannabis say the risks are low compared with those of alcohol and tobacco. But many doctors say that the risks outweigh the benefits, and the British Medical Association said yesterday that the latest treatment figures strengthened its opposition to the decision to downgrade the drug.

A BMA spokesman said: “This is a drug that is mostly smoked, so that can cause lung damage and cancer. There are also concerns about the potential negative effect cannabis has on users’ psychiatric state.”

Joint operation

20.9 Percentage of 16 to 24-year-olds who used cannabis, according to the 2006-07 British Crime Survey
14 years The maximum penalty for supplying cannabis, with unlimited fines
208,357 The number of cannabis plants seized by police and Customs in England and Wales in 2005

Source: Times database

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