This from the BBC News website:
Nightclubs get NHS drugs advice
Nightclubs are being given guidance from NHS specialists on spotting the symptoms in someone who may have taken drugs and when to summon medical help.
The advice, co-written by doctors, police officers and bar owners, was published in the journal Substance Abuse Treatment, Prevention and Policy.
One author said some staff had avoided calling an ambulance for a clubber as they feared losing their licence. Drug charities said they hoped clubs would follow the rules where possible.
The study authors found that the main drugs linked to ill-health among clubbers were GHB and stimulants such as ecstasy and cocaine.
These produced symptoms ranging from problems with breathing having taken GHB, to high temperature, heart rate and blood pressure with the stimulants.
Many clubs now have designated medical rooms where people who have fallen ill while on the premises can be assessed and treated.
Dr David Wood, from the Poisons Unit at Guy's and St Thomas' NHS Foundation Trust, in London, helped write the guidance.
He said that he wanted to work to improve the care of clubbers before they reached hospital, including extra training for club first-aid staff.
Their guidance advised "club medics" to call for an ambulance if the patient showed signs of a long list of symptoms, including being unresponsive, having chest pain similar to a heart attack, or high blood pressure.
It urged them to make the call if they were in any doubt about the condition of a clubber.
Dr Wood said: "The guidelines are designed to ensure that individuals with a significant toxicity in these categories are easily identified and that an ambulance is called so they receive appropriate and timely assessment and management in a hospital environment.
"In the past, club owners and promoters have been reluctant to call an ambulance because of concerns this could affect their licence."
A spokeswoman for the London Drug Policy Forum said the advice was welcome and would be included in the next edition of its "Safer Nightlife" booklet for clubs and club staff. She said: "The fact is that people do take drugs when they go clubbing, and we all need to work together to keep them as safe as possible."