A major factor in many ecstasy-related deaths is the dehydration and overheating that can result when ecstasy is taken in conjunction with all-night dancing. Ecstasy increases body temperature, blood pressure and heart rate, which can lead to kidney or heart failure, strokes and seizures. Ecstasy may cause jaundice and liver damage.

People with high blood pressure, heart or liver problems, diabetes, epilepsy and any mental disorder are the most vulnerable to the potential dangers of ecstasy. Part of the danger is that people may not be aware that they have these conditions, and the effects of ecstasy can trigger symptoms.

As with all illegal street drugs, the purity and strength of ecstasy can never be accurately gauged. When you take ecstasy, you don't know what you're taking, or how it will affect you.

Combining ecstasy with other drugs, illicit or prescription, may cause a toxic interaction. There are several prescription medications know to interact with ecstasy. There include a certain kind of antidepressant called monoamine oxidase inhibitors (MAOIs), and ritonavir, a protease inhibitor used to treat HIV.

Driving or operating machinery while under the influence of ecstasy, or any drug, increases the risk of physical injury to the user, and increases the risk of injury to others.

Tolerance to ecstasy builds up very quickly. this means the more often you take ecstasy, the less effect the drug has. Taking more of the drug may not achieve the desired results, as frequent ecstasy use depletes serotonin and other brain chemicals that give the ecstasy "high."

While there is little evidence to indicate that MDMA can produce physical dependence or withdrawal symptoms, it's not uncommon for the drug to take on an exaggerated importance in people's lives.