If you came here thinking there would be a simple answer to a simple question, you were not correct – there’s a lot that goes into coming up with a response, starting with the definition of dangerous.
In a now-infamous paper published in 2010, 16 parameters of harm were considered when classifying the harmfulness of drugs, both legal and illegal. Each drug’s effect on the user, on others and on society as a whole were taken into consideration. The list included the likelihood of mortality, dependence, mental impairment, loss of tangible items, physical injury, and criminal activity – but, as one of the paper’s author’s says, that doesn’t mean there weren’t still disagreements.
“There are two elements to it. Deciding on the various harms – the 16 parameters – most experts agree on that. The more interesting question is how much you care about each of these different rankings; this is where the weightings come in. This could vary greatly depending on the group’s opinions.”
Basically, what drug comes out as the “most dangerous” has a lot to do with the people making the list.
Still, most experts agree that due to its harm to others (including the wider economy), alcohol is far and away the world’s most dangerous drug.
Heroin and crack cocaine came in second and third, with pot 8th on the list, and ecstasy and LSD among the least harmful.
Above marijuana? Tobacco (6th).
Alcohol wins (loses?) due to the fact that it causes a plethora of diseases, transportation accidents, and increases promiscuous activities (which poses health risks). Plus, it costs taxpayers dearly to remediate these harms.
Many people might disagree, given that alcohol is legal and many of the other drugs listed are not. And then there’s the fact that drugs and policing can be used as political tools.
Cannabis is nowhere as dangerous as alcohol, according to actual scientific evidence, yet it costs millions of dollars to enforce weed laws on the books. If the U.S. were to legalize it across the board, governments would see profits in the billons of tax dollars and take a major asset out of the hands of criminal organizations in the process.
All drugs are dangerous to some degree, but while alcohol abuse is often seen as a health issue, heroin addiction is treated as criminal behavior due to the drug’s legal status – that has nothing to do with its danger level. Which is to say, the idea that a drug is more dangerous because you can get arrested for using it is completely unfounded.
tl;dr: Alcohol. But you’re going to want to think long and hard before using at all, if you ask me.