Dennis Quaid says cocaine once consumed his life — here's how the drug hijacks your body and mind

In an interview Monday with NBC’s Megyn Kelly, actor Dennis Quaid opened up about the years he spent battling a severe cocaine addiction in the early days of his career. “I grew up in the ’60s and ’70s and there was a completely different attitude about it back then — it was even in some movie budgets,” he told Kelly. “But, you know, I kept roaring on. I was basically doing cocaine pretty much on a daily basis — I mean, you’re in the ’80s.”

Quaid told Kelly that the addiction led to many sleepless, agony-filled nights — all while he was maintaining a burgeoning career. “I spent many, many a night screaming at God to please take this away from me and I’ll never do it again because I’ve only got an hour before I have to be at work,” the 64-year-old said. “And then about 4 o’clock in the afternoon I would go, ‘That’s not so bad.'”

Eventually, while engaged to Meg Ryan, he checked himself in to rehab. “I had what I’d call a white-light experience,” said Quaid. “I saw myself either dead or losing everything that meant anything to me.” After a stint in rehab and a decade’s worth of self-exploration, Quaid returned to stardom with his role as Lindsay Lohan’s dad in The Parent Trap.

Quaid’s relationship with the drug is over, but he’s far from the only one to get trapped by its euphoria. Just this week, talk-show host Wendy Williams opened up about her own battle with the drug, calling herself a “functional addict” with an addiction so strong it took a “miracle” to stop.

So what is actually happening that makes those dependent on the drug still able to function — often on little to no sleep? The answer lies in the way cocaine works in the body.

Derived from a coca plant native to South America, cocaine is a highly addictive drug that can prove fatal in large doses. First introduced to the U.S. in soda form (think: Coca-Cola), it’s a substance that the National Institutes of Health estimates 1.5 million Americans currently abuse. According to the National Institute on Drug Abuse (NIDA), the drug itself works by altering the brain’s levels of certain chemicals — chief among them dopamine, the “feel-good hormone.”

NIDA explains the mechanism this way: “Normally, dopamine recycles back into the cell that released it, shutting off the signal between nerve cells. However, cocaine prevents dopamine from being recycled, causing large amounts to build up. This flood of dopamine in the brain’s reward circuit strongly reinforces drug-taking behaviors, because the reward circuit eventually adapts to the excess of dopamine caused by cocaine, and becomes less sensitive to it. As a result, people take stronger and more frequent doses in an attempt to feel the same high.”

In the short term, use of the drug can lead to extreme feelings of elation, increased heart rate, restlessness, and paranoia. But long-term it can create a host of problems, from loss of sense of smell to insomnia. While scientists are still researching exactly why cocaine and other stimulants cause sleep loss, recent studies have shown that the surge in dopamine affects the body’s circadian rhythms. Since circadian rhythms regulate sleep patterns, this leads to difficulty both staying and falling asleep — something Quaid experienced firsthand.

The good news, as with other drug addictions, is that it’s treatable. Several medications can be used to help someone who is severely dependent recover, and many people — like Quaid and Williams — go on to lead healthy lives. If you or someone you know is suffering from an addiction, don’t hesitate to seek help.

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