The number of teens who have ended up in the emergency room after using MDMA – the drug present in both Ecstasy and Molly – has more than doubled in recent years, Medical Xpress reported.

According to a report released by the U.S. Substance Abuse and Mental Health Services Administration, emergency room visits among people under age 21 related to the use of MDMA have increased by 128 percent between 2005 and 2011.

"This should be a wake-up call to everyone, but the problem is much bigger than what the data show," said Steve Pasierb, president and CEO of The Partnership at Drugfree.org. "These are only the cases that roll into the emergency rooms. It's just the tip of the iceberg."

Ecstasy is known for producing a feeling of euphoria and increased energy among users, according to Medical Xpress. However, the drug can also be accompanied by dangerous side effects, including overheating, rapid heartbeat, increased blood pressure and dehydration – which can potentially result in kidney or heart failure.

Experts suspect that the increasing popularity of Molly, a powder-form of MDMA, may be driving the surge in emergency room visits.

"When (MDMA) was in a finished pill, it was difficult to tamper with," Pasierb said. "But now that it comes in a powder form, you might have an unscrupulous dealer who cuts it with speed or some other substance."

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