This is your brain on molly

You’re dancing, flashing lights everywhere. The music is thumping. You’re having a great time. And then you drop some molly, and the party just gets better.

You start to feel goooood, like nothing in the world can get you down. You have more energy, and your inhibitions fade away. That cute dude next to you is suddenly looking hotter, so you go over and start gyrating with him.

Life is super, and that’s because molly–or ecstasy, as it’s better known among the olds–has played tricks on your brain. The active ingredient is MDMA. Short for 3,4-methylenedioxy-methamphetamine, MDMA is both an amphetamine and a hallucinogen. It makes you feel happy (and maybe a little sexy) because it changes the way the nerve cells in your brain normally communicate.

Those cells, or neurons, are sending each other messages all the time in reaction to what you’re seeing and experiencing in the world with chemical messengers called neurotransmitters. When you see someone you like, for example, a neuron releases a tiny package filled with the neurotransmitter dopamine. The “feel good” dopamine makes its way to another neuron designed to grab onto it, and when it does, it registers as that wonderful feeling that is pleasure.

When MDMA hits the brain, it jacks up the amount of these messages being sent around your brain. More specifically, it increases the activity of three of your neurotransmitters — serotonin and dopamine, which are known as “feel good” molecules — and your norepinephrine, which is often involved in fight-or-flight responses.

Serotonin, which is well-known for influencing mood, gets the biggest boost when someone takes MDMA so researchers think that it’s the key to the drug’s euphoric effect. Serotonin has also been shown to trigger the release of oxytocin and vasopressin, two hormones involved in developing feelings of love, trust and sexual arousal, which again might help explain the way people act while tripping on E.

(Because molly lowers your inhibitions and makes you feel sexy, you may be more likely to get naked with someone without using protection. That often leads to less than ideal situations.)

That’s step one. Neurons typically release more neurotransmitter than is needed, so neurons have a way of slurping the excess back up. But MDMA blocks that, prolonging the amount of time serotonin, dopamine and norepinephrine are hanging around. (Other drugs, like cocaine and flakka, work in much the same way.) So, for a while, that makes you feel like you’re on top of the world.

But that only lasts somewhere between three and six hours. Because your brain can’t recycle the serotonin, dopamine and norepinephrine it released, you end up depleting your brain’s bank of these neurotransmitters. You’re releasing more and you can’t recycle what you’re not using. It’s a lose-lose. That’s probably why some people end up feeling like crap when they come down from the high. They’re in the red when it comes to their feel-good molecules. Some users, for instance, experience confusion, depression, sleep problems, drug craving, and anxiety.

The verdict is still out on whether MDMA is addictive and on how harmful is to the brain. A recent study found that MDMA didn’t cause any bad long-lasting cognitive deficits, like memory loss, but it was a relatively small study. Others have found that the drug does negatively impact the brain, but the caveat there is that most of that research didn’t account for other factors that affect brain function, like lack of sleep or taking other drugs.

In recent years, researchers have also started to explore using MDMA to treat mood disorders like post-traumatic stress disorder. According to a National Institutes of Health database, there are at least nine clinical trials using MDMA as a therapy for PTSD.

But before you go reaching for that molly, thinking science is saying it’s safe-ish, keep in mind that chances are that what you’re getting isn’t pure MDMA. It’s often laced with cathiones, or bath salts, and other substances. And be honest, you’re also likely to drink, smoke weed or try other drugs while on molly, which can be dangerous. Earlier this year, 12 Wesleyan students ended up in the hospital after taking molly.

Worried parents everywhere can take some comfort in knowing that the percentage of kids trying ecstasy has been on the decline. It is popular with the the youngs — the average age of first-time users was 20.5 years — but less popular than it used to be. According to the 2013 National Survey on Drug Use and Health, roughly 750,000 people tried the drug for the first time, down from 922,000 in 2011. Though who knows what will happen after the strong endorsement the drug got in the summer hit Magic Mike XXL. After the film’s “male entertainers” take molly one afternoon, this happens:

The movie did stay true to science, though. Spoiler: Magic Mike’s crew makes a poor decision that involves touching, and everyone gets cranky and depressed after the molly wears off.

For more on drugs, check out Drug Wars.

Daniela Hernandez is a senior writer at Fusion. She likes science, robots, pugs, and coffee.