Legal highs are so popular the only option is to "educate people who are using them" about how they can make safer choices about the drugs they take, an addiction specialist told Good Morning Britain.
Associate medical director of the CRI, David Bremner, said: "In a matter of days a new drug will be released that will have one molecule changed that then beats the law so that it is no longer illegal...all we can do is educate people who are using them on how to make safer choices."
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Sir Vince Cable has become the new leader of the Liberal Democrats, after no other nominations were put forward.
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Gordon Brown has said forced child migration schemes that continued until the 1970s amounted to "government-induced trafficking".