I just saw a study that was published in The Lancet, one of the oldest peer-reviewed medical journal, about the harmfulness of drugs that are commonly misused. They used nine different measures in three major categories of harm: physical harm, dependence, and social harm. Two separate groups of experts were used to score the drugs. The first was a group of psychiatrists who specialize in addiction and the second was a broad group of chemists, pharmacologists, legal and police experts, and others who deal with addiction.
Here is their ranking of all the drugs based on their mean score of harmfulness. I wasn't particularly shocked to see that cannabis is lower than both alcohol and tobacco, but I was surprised that LSD and ecstasy were so low.
