A report commissioned by three south London boroughs into drug use during sex has highlighted significant risks to the sexual and mental health of gay and bisexual men.

Councils in Lambeth, Southwark and Lewisham – boroughs which have a high population of gay men – said they are are determined to tackle the growing problems associated with ‘chemsex’.

The findings of the report, produced by experts in HIV and sexual health at the London School of Hygiene & Tropical Medicine, will inform the response to the problem.

Health experts have previously raised concerns that chemsex, or sex under the influence of drugs such as crystal methamphetamine, GHB/GBL and mephedrone, could be behind rising rates of HIV and STIs in gay men.

Lambeth has the highest prevalence of HIV in the UK (14 per 1,000 residents aged 15-59) and Southwark has the second highest (12 per 1,000).

Councillor Jim Dickson, Lambeth’s Cabinet Member for Health and Wellbeing, said: “This research provides essential insight into the complex needs of this particular at risk group of our local residents.

"It will enable us to work with partner organisations to find new approaches to reducing harm and to support the health and wellbeing of affected men.”

The Chemsex Study, published on Friday, is the first research of its kind in the UK to look at the complex relationship between drug use and sexual behaviour and documents the harms that some gay men experience.

Majority of sex drug users "not happy with sex lives"

Report lead author, Dr Adam Bourne from the Sigma Research team at the London School of Hygiene & Tropical Medicine, said: “A vulnerable section of society is using new drugs in new ways that is putting them at serious risk.

“Although our study shows that chemsex is uncommon overall, there is a need for specialist support for men who have sex under the influence of these drugs.

“Gay and bisexual men need better information and advice as well as access to gay-friendly drug and sexual health services that are able to address the psychosocial aspects of chemsex.

“We also need to work with social and sexual networking apps and websites to ensure they are supporting health promotion and harm reduction to their users.”

Researchers analysed survey data from 1,142 gay and bisexual men living in Lambeth, Southwark and Lewisham and conducted in-depth interviews with 30 gay men from the area.

They found that although chemsex was reported to increased sexual arousal and facilitate more adventurous sex, many men were using drugs to mask self-esteem or self-confidence issues.

The majority of men were not happy with their sex lives and wanted a long-term partner for more intimate and emotionally connected sex.

Around a third of men interviewed found it difficult to maintain control of their behaviour or negotiate safe sex while under the influence of drugs and had unprotected sex with high risk of HIV/STI transmission, which they regretted.

Overdosing, panic attacks, convulsions and sexual assault were all associated with chemsex.

Many men also felt that the large amount of time they spent engaging in chemsex was detrimental to their social relationships and career progression.

Public Health England has raised concerns about rising HIV and sexually transmitted infections (STIs) in men who have sex with men.

A forthcomingwill aim to address these issues and set a strategic direction for improving the sexual health of residents.