The war on drugs has been bad for the world's health. Concentrating on criminalizing the producers, tra?ffickers and consumers of narcotics, it has failed to reduce supply. UN figures show that drug consumption during the decade after 1998 rose, with a 34.5 per cent increase in the number of opiate users, 27 per cent rise in cocaine users, and 8.5 per cent rise in cannabis users.

Most drug users do not receive effective treatment and care, and where treatment is available, it is often inferior to that afforded to other diseases.

Experts are now calling for an orientation away from the punitive strategy -- especially for users -- towards a public health approach that could help reduce the damage.

The detrimental consequences of drug use are well documented.

'Hard drugs' that users inject, such as heroin, bring with them a plethora of health risks. Sharing needles can lead to the transmission of infectious diseases such as HIV and hepatitis. A report from the Global Commission on Drug Policy in June suggested that the war on drugs is hampering the fight against HIV/AIDS, with the fear of arrest driving users underground.

Restricting the provision of sterile syringes and needles to drug users results in increased sharing, while the prohibition of opioid substitution therapy and other evidence-based treatment and the lack of HIV prevention measures in prisons makes the problem worse.

Evidence also suggests that countries such as Britain, Switzerland, Germany and Australia, which implemented harm-reduction strategies from the onset of the HIV epidemic in the 1980s have a much lower prevalence of HIV among drug users, compared with countries such as the US, Portugal and France that were slower off the mark. Countries that did nothing have extraordinarily high incidences of HIV among intravenous drug users, such as Thailand, where prevalence is above 40 per cent.

The current system offers no control over the content or quality of illicit drugs either, which means potency is likely to vary with each dose, increasing the chances of overdose. Lack of regulation also permits adulteration with criminal gangs mixing drugs with other possibly toxic substances to make them go further.

So-called legal highs add to the confusion. Just because they are legal, it does not mean they are safe: they are just not yet on the list of illegal substances. Yet continuously adding to the list of banned substances makes it increasingly unworkable and as soon as a new 'legal high' is added to the list, users find another substance outside the classification system to replace it.

Finally, 'soft drugs' such as cannabis are not safe. Commonly reported problems associated with their use include memory loss, reduced spatial awareness, increased anxiety, depression, and difficulty with problem solving. There are also longer term health issues similar to those associated with smoking cigarettes, such as heart disease and lung cancer.

Would a change in approach reduce damage to health?

It is difficult to say with certainty that reforming drug laws would decrease the health risks associated with illicit drug use, but there is no denying that the current approach is failing to prevent the deaths of many thousands of people each year.

Estimates suggest that in California -- where cannabis is now legally accessible to people with cancer, AIDS and other chronic illnesses when approved by a doctor -- an extra $1.3 billion would be generated each year in tax revenue if cannabis were to be made legal for non-medical purposes. Some estimates suggest that it could save a further $1 billion a year by eliminating arrests, prosecutions and imprisonment of non-violent offenders.

However, any change would not alter the direct health risks associated with its use.

Regulation and control may help reduce the health hazards associated with adulteration and injection of toxic substances and there is evidence that a change in approach might help reduce blood-borne disease transmission among those who inject drugs. But whether it would reduce the likelihood of overdose remains uncertain, and it is unlikely to reduce addiction.

Ultimately, applying a public health focus to tackling drugs might reduce some health concerns associated with illicit use but implementing an approach based upon it would be difficult.

Whatever change takes place, it should not promote the normalization of drug use. Shifting away from the prohibition approach -- whether towards decriminalization while continuing to pursue drug-related organized crime, or towards legalization and regulation of drugs -- would shift responsibility to the health sector. But could the public health sector cope? Such an approach would create a significant challenge for policy-makers.

Educating young people about the dangers of taking drugs is also important.

However, one argument put forward to justify a change in approach is that the way in which we classify drugs bears almost no relation to their relative degrees of harmfulness to health, and that legal substances such as tobacco and alcohol cause more deaths per year than illicit drugs. There is no denying that the many different ways of classifying the harmfulness of drugs, compiled by many different sets of people, only further adds to the confusion.

As the former British government drugs adviser Professor David Nutt suggests: 'Children are much smarter than politicians. We need to tell them the truth, not lies about how deadly drugs are. This is not something that can be done overnight. It will take generations.'

Professor Nutt put the issues in clearer context when he stated in 2009 that statistically, alcohol and tobacco are more dangerous than LSD -- food for thought as we think through the implications of changes in the war on drugs.

Ian Perrin and David L Heymann, Centre on Global Health Security, Chatham House

(c) 2012 Tribune Media Services, Inc.