Taking just one ecstasy tablet may be enough to make you depressed, a study suggests.
Ecstasy is a popular drug among clubbers
Researchers at London Metropolitan University have found that people who take ecstasy are more likely to suffer depression compared to non-users and even people who use other drugs.
Their study also indicates that heavy users of the drug are at risk of becoming clinically depressed.
The researchers believe ecstasy has a long-lasting impact on key chemicals in the brain, which regulate mood.
The findings are based on a study of almost 600 working professionals. They each filled out a form detailing previous drug use and overall mood.
The researchers split these people into three different groups - those who had only taken ecstasy; those who took other drugs; and those who have never taken drugs.
Anybody who had taken drugs in the previous three weeks were excluded. This was designed to ensure the pharmacological effects of the drugs did not influence the study.
The researchers found that people who took ecstasy were generally more depressed than people in either of the two other groups.
"People who said they had taken just half a tablet had high depression scores compared to people in the other groups," said researcher Lynn Taurah.
The study also revealed that depression levels among ecstasy users were linked to the amount of drugs they were taken.
Ms Taurah said she believed the different depression scores could be linked to the effects of ecstasy on the brain.
"I think it could be argued that people who take ecstasy are perhaps generally more depressed.
"But I think this is unlikely simply because we did not see similar rates of depression in those who took other drugs," she told BBC News Online.
She suggested the results tied into previous studies which have indicated that ecstasy can affect key brain chemicals.
"There is a lot of data in animals showing that ecstasy damages the neurotransmitter for serotonin, which is known to be involved in depression."
Serotonin also plays an important role in regulating memory and behaviour. The researchers are now looking to see if these are also impaired on people who take ecstasy.
"We think there may be a connection, said Ms Taurah.
The findings were presented at the British Psychological Society annual conference in Bournemouth.