The topic legalization of use of drugs sparks a debate whenever discussed. The results of several studies conducted by authorities worldwide add some flavor to the debate. Here is a study conducted by David J. Nutt, MD, Imperial College, London, United Kingdom, and the Independent Scientific Committee on Drugs, and colleagues. The results of the study was published in The Lancet
The multicriteria decision analysis (MCDA) model assessed 20 drugs most commonly used in the United Kingdom for their potential to cause 16 harms:

* Drug-specific mortality;
* Drug-related mortality;
* Drug-specific damage;
* Drug-related damage;
* Dependence;
* Drug-specific impairment of mental functioning;
* Drug-related impairment of mental functioning;
* Loss of tangibles (job, housing, income, etc);
* Loss of relationships;
* Injury;
* Crime;
* Environmental damage;
* Family adversities (eg, family breakdown, child neglect, etc);
* International damage;
* Economic cost; and
* Community.

Drugs were scored on a points scale of 100, with 100 being the most harmful drug and zero being something that caused no harm at all.

The study found that overall, according to the new MCDA model, alcohol was the most harmful drug, with an overall harm score of 72. Heroin came second, with a harm score of 55, and crack, with a harm score of 54, came third.

Heroin, crack, and crystal meth (harm score, 33) were the most harmful drugs to the individual, whereas alcohol, heroin, and crack were the most harmful to others.

Harm Scores

The overall harm scores for the other drugs that were assessed were:

* Cocaine – 27;
* Tobacco – 26;
* Amphetamine/speed – 23;
* Cannabis – 20;
* γ-Hydroxybutyric acid – 18;
* Benzodiazepines (eg, valium) – 15;
* Ketamine – 15;
* Methadone – 14;
* Mephedrone – 13;
* Butane – 10;
* Khat – 9;
* Ecstacy – 9;
* Anabolic steroids – 9;
* Lysergic acid diethylamide – 7;
* Buprenorphine – 6; and
* Mushrooms – 5.

According to the model, not only was alcohol the most harmful drug overall, it was almost 3 times as harmful as cocaine or tobacco and 5 times more harmful than mephedrone, a drug that was legal in the United Kingdom before it was made a controlled substance in April 2010. Ecstasy was only one-eighth as harmful as alcohol, the investigators reported.