Students on the appeal of using legal highs
12 February 2014 Last updated at 04:10 GMT
There has been a rise in the number of deaths linked to so-called "legal highs".
Sixty-eight people died after taking new psychoactive substances in 2012, according to post-mortem results compiled by St George's, University of London. There were just 10 such deaths in 2009.
Many of these are substances are specifically made to mimic the effects of illegal drugs - but are chemically different enough to side-step the law and are on sale openly on websites and high streets across the country.
Suppliers can sell them legally as long as they write "not for human consumption" on the packets.
Tulip Mazumdar has been to meet a group of social workers, attending a drug workshop run by the Kent-based drug and alcohol charity KCA.
These social work students say they have never touched legal highs, but understand why some people find them appealing.