There's a warning that 2016 may be the most dangerous time to take MDMA for a generation.

The Global Drug Survey 2016 polled 50,000 ecstasy users and found much stronger pills and powders are in circulation.

It's leading to an increase in hospital admissions, according to researchers, because users are not always aware of purity levels.

And young women are more likely to end up in an emergency department.

Dr Adam Winstock from the Global Drug Survey, or GDS, explained to Newsbeat why the new higher levels are such a problem.

More related stories Ecstasy and MDMA is 'getting stronger'

"A dose of about 80mg of MDMA for most people, without tolerance and assuming average body weight, gives them the pleasurable effects of energy, euphoria and empathy," he explained.

Higher doses tend to leave people feeling too wasted for too long... Dr Adam Winstock Global Drug Survey

"[These] outweigh the negative effects that become more common with bigger doses such as nausea, panic, paranoia, agitation and gurning.

"Higher doses tend to leave people feeling too wasted for too long and being less able to enjoy the people around them and their environment.

"The current average dose of MDMA used in a session across many countries is over 200mg.

"GDS thinks for most people this is too much."

It says higher dose pills and high purity MDMA powders can make it very easy for users to take too much.

Ecstasy health risks It can make you anxious, frightened and paranoid



It tightens your jaw muscles and can make you gurn



It raises your heart rate



Dancing after taking it can make you very dehydrated



Long-term use can cause depression, heart disease and liver and kidney damage

This backs up a major report from international drug experts.

The European Monitoring Centre for Drugs and Drug Addiction warned in May that ecstasy and MDMA is getting stronger with dangerously "pure" pills and crystals in circulation.

Its latest report highlights a "recent resurgence in use of MDMA in Europe and increased availability of high-strength MDMA tablets and powders".

"2016 might be the worst time to start taking MDMA in a generation," Dr Adam Winstock told Newsbeat.

"MDMA has never been so plentiful and as GDS trend data shows, more and more people are using it.

"The rising popularity of EDM and dispersion of MDMA from the dance floor to mainstream drug culture has coincided with resurgence of MDMA availability."

The authors of the reports say it is time people learned how to be safer. Dr Winstock told Newsbeat that if people chose to take the drug, there were three pieces of advice he wanted people to listen to.

"People should aim to use less MDMA. If you are going to re-dose, you should do so after you have peaked to reduce the risk of higher dose unwanted effects

"Try not to use more often than once a month.

"Stay cool and hydrated and try to avoid mixing with other drugs or alcohol."

There is BBC Advice on ecstasy and MDMA.

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