The recent deaths of two teens have been blamed on the legal drug mephedrone, which is marketed as plant fertilizer, and causes "headaches, palpitations, nausea, high blood pressure, a burning throat, nose bleeds and purple joints, weight loss and insomnia."
"The drug, which comes in the form of a powder, tablets, crystals or liquid, is often sold cheaply via the internet, where it can be marketed as plant food, another name for the substance."
The BBC says that the drug, nicknamed "meow meow", was due to come under review last year by health officials, but a fight over the classification of other drugs put the review on hold:
"The work of the committee on legal highs stopped following the dismissal of its chief drugs adviser Professor David Nutt last October. He was sacked after publicly disagreeing with the government's decision to reclassify cannabis as a Class B drug and not to downgrade ecstasy."
For possession of Class B drugs, like weed and amphetamines, a person can do up to five years in prison.