A clinic helping people who use or have used club drugs has opened in west London.
Doctors say it will offer treatment for those with problems caused by drugs such as ketamine, ecstasy and mephedrone.
Users of such drugs may think treatment services are geared towards crack or heroin and not seek help, it said.
The NHS clinic, based at the Chelsea and Westminster Hospital in south-west London, has funding for two years.
It is staffed by doctors, nurses, drug workers, psychologists and HIV workers.
Clinic founder Dr Owen Bowden-Jones said: "The health risks associated with excessive use of club drugs are under-estimated by many people.
"Little is known about the potential problems of the newer drugs."
Dr Bowden-Jones said most existing services focused on alcohol, heroin and crack cocaine use.
"Many people experiencing club drug problems do not see current treatment services as well equipped to help them," he added.
"As a result they do not seek treatment."
The new clinic was piloted for five months and received more than 70 referrals.
It has the capacity to see nine new patients every day.
A similar unit opened at the South London and Maudsley NHS Foundation Trust in 2009.