MDMA: acute effects of ecstasy on T-cell numbers and function

Sean Hosein, for Canadian AIDS Treatment Information Exchange

The popular recreational drug ecstasy – or more simply E – causes users to experience feelings of bliss. Although users perceive ecstasy as safe, this drug does have a dark side.

There have been worrying reports of long-term memory problems among some former ecstasy users. More recently, researchers in the European Union have been studying the impact of ecstasy on the immune systems of mice and people and have found some troubling data.

Study details

Researchers enrolled 17 healthy (HIV-uninfected) male subjects for a series of short, placebo-controlled studies of ecstasy. Subjects received 100mg ecstasy once or twice over a period of 24 hours. Blood samples were collected before, during and after the study.

Results: a single dose

The researchers found that a single dose of ecstasy (100mg) taken by mouth caused a dramatic fall in the level of immune system cells called T cells, which are needed to help fight infections. The number of a specific group of T cells, called CD4+ cells, decreased by about 30% within hours after a single dose of ecstasy. Fortunately, within a day after taking this dose, CD4+ cell levels returned to normal.

Results: two doses

Among subjects who received two doses of the drug, four hours apart, the decline in CD4+ cells was even more serious, reaching a level 40% below normal. Although a day later T-cell levels rose, they did not return to normal.

Another important finding is that ecstasy clearly reduced the ability of T cells as well as other immune system cells to fight infections.

Why is ecstasy not immune friendly?

Perhaps these results should not be surprising as ecstasy is chemically related to another group of chemicals called amphetamines. This group of drugs does not enhance the health of the immune system. The research team also found that exposure to ecstasy causes the body to produce increased amounts of the hormone cortisol. This hormone probably caused the CD4+ cell count to temporarily fall because these cells moved from the blood to the lymph nodes and tissues. They returned to the blood once cortisol levels returned to normal. Higher than normal cortisol levels may also have been the reason that the immune cells’ ability to fight infections was reduced. In people with HIV/AIDS who use ecstasy, the drug therefore has the potential to increase levels of HIV.

Furthermore, ecstasy can rise to dangerous levels among patients who also use anti-HIV drugs known as protease inhibitors and non-nucleoside reverse transcriptase inhibitors.

Another point to consider is that the researchers used relatively pure ecstasy. In the real world, it is not uncommon to find ecstasy blended with a small amount of amphetamine or LSD. Unlike the situation with licensed drugs, no independent agencies have the authority to conduct quality control tests to ensure that chemical contaminants are removed from the final product. Nor are there any agencies that have the power to force ecstasy manufacturers to conduct studies on the impact of this drug on the health of users. Given the increasing popularity of ecstasy, harm reduction experts have their work cut out for them.


  1. Pacifici R., Zuccaro P., Farré M., et al. Effects of repeated doses of MDMA (-Ecstasy -) on cell-mediated immune response in humans. Life Sciences 2001; 69:2931-2941.
  2. Connor T.J., Connelly D.B. and Kelly J.P. Methylenedioxy-methamphetamine (MDMA; -Ecstasy -) suppresses antigen specific IgG2a and IFN-gamma production. Immunology Letters 2001; 78(2): 67-73.

Source: CATIE – Canadian AIDS Treatment Information Exchange.

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