Nick Bonnie, 30, collapsed at a nightclub in Manchester in the early hours of Saturday.
Mr Cameron said: "This is a tragic death. We've seen too many of these".
When asked if the Government has a grip on its drugs policy, he said: "The focus of Government has quite rightly been on education...and treatment".
He added that he disagreed with the Chief Constable of Durham's call for some drugs to be decriminalised as "it would make them more available and lead to more problems".
More top news
A newborn baby girl has been killed by dogs after they attacked her while she was lying on a sofa.
It is plausible to say we haven't had our last vote or say on the nature of Britain's relationship with the EU.
After Roy Hodgson's resignation following England's humiliating exit from Euro 2016, who are the leading contenders to replace him?