British studies show ecstasy can cause lasting psychological damage

One study suggested ex-users were not properly able to regulate levels of the brain chemical serotonin, which has a powerful effect on mood. They also displayed enhanced levels of aggression which were more pronounced the longer they had taken ecstasy.

Another study revealed that heavy use, with or without other drugs, was strongly associated with psychological problems linked to serotonin, such as anxiety, phobia and negative feelings. Serotonin is an important neurotransmitter, a chemical which enables brain cells to send messages to each other.

Valerie Curran, from University College London, tested the serotonin system of both current and former ecstasy users, using a natural substance called tryptophan which provides the dietary raw material for making serotonin.

Curran's team gave 96 men drinks that either starved them of tryptophan or offered them an extra amount. Former ecstasy users were significantly more sensitive to this manipulation than either non-users or current users. Their performance in memory and other mental tests was unusually impaired by lack of tryptophan, and enhanced by extra tryptophan.

"We think this may be happening because of changes to their serotonin system caused by taking ecstasy, which could involve the loss of neurones. Alternatively they may have been more sensitive than average prior to taking ecstasy, but I think that is unlikely," Curran said.

Animal studies have shown that the brain chemistry of monkeys remains disturbed four or five years after they are given ecstasy. There was also a significant link between aggression and ecstasy use in the past, Curran said.

"The ex-users were more aggressive than the current users, and those scores correlated with the length of time they had taken the drug," she said, adding that hostility levels fell off as time passed. "I think our study implies that there may be long-lasting consequences of using ecstasy that persist after people stop taking it," Curran said.

In another study, Andrew Parrott and colleagues from the University of East London collected data from 758 young people from London, Manchester and Rome. The study found that ecstasy and multi-drug taking was most significantly associated with a range of disorders such as anxiety, anger and hostility, phobia, and "total negative feelings".

The scientists concluded the results could be indicative of impaired serotonin functioning. A third team led by Phillip Murphy, from Edge Hill College of Higher Education, Lancashire, showed that ecstasy users may experience depression and aggression as well as pleasurable feelings from taking the drug.

These effects were more commonly experienced by people who were older and had used the drug for longer. Ecstasy is technically known as MDMA, or 3,4-methylenedioxymethamphetamine. It was first synthesised in 1912 and patented in Germany in 1914.

Largely forgotten until the 1970s, it was rediscovered by psychiatrists and therapists advocating "psychedelic therapy" and was used as an adjunct to psychotherapy. In the 1980s MDMA began to be used non-medically, particularly in Texas, under the name ecstasy.

The drug, which gives users a feeling of euphoria and increases self-confidence, is normally taken while out dancing at nightclubs. The tablets are usually printed with symbols such as hearts, cartoon characters or numbers, and prices for tablets range from about four to 20 pounds (six to 30 dollars) in Britain.

A number of deaths have been attributed to use of the drug and its tendency to cause users to drink inordinate amounts of water.

(la/dpa)