Exclusive | I used to be a happy drunk — Ozempic made me a sad one, and the hangovers are horrendous

Welcome to The Thin Line, The New York Post’s series about the darker side of GLP-1 drugs. Though GLP-1 agonists sold under brand names like Ozempic have helped millions of people lose weight, manage diabetes and improve other health conditions, they are not without risks. Check back for more stories about the lesser-known downsides of these wildly popular medications.

Trey Luker-Stewart was ready for a change.

“For the longest time, I was using eating as an activity,” the 29-year-old Texan told The Post. “We don’t have mountains or an ocean here in Dallas. We just love to shop, eat and drink.”

So two years ago, he decided to break the cycle. Like millions of Americans, Luker-Stewart went on a GLP-1 weight-loss drug — and quickly watched 60 pounds melt away.

But the slimmer waistline came with a curveball he didn’t see coming. “I was always a super happy drunk, but once I got on Ozempic, I wasn’t,” he admitted. “I became a lot more emotional.”

Suddenly, the carefree nights he spent sipping drinks at the neighborhood watering hole with friends started to feel anything but relaxing.

“Something that was once a fun thing to do now made me anxious and upset,” Luker-Stewart said. “I start overthinking everything and my feelings get hurt easier.”

The next morning is even worse.

“Before, I could wake up after drinking at 7 a.m. and go to the gym and be productive,” Luker-Stewart said. “But once I started taking a GLP-1, I was down for the count ‘til lunchtime.”

And that was after just one or two drinks.

For Luker-Stewart, a real estate agent who also owns a bar, Ozempic — and later tirzepatide, the active ingredient in drugs like Mounjaro and Zepbound — hasn’t just affected his nightlife; it’s taken a bite out of business, too.

“In Dallas overall, we’ve seen a 35% drop in alcohol sales across the board, and I think a lot of that has to do with GLP-1s,” he said. “I know I’m not the only one that feels this way when they go out.”

Doctors say he’s onto something.

“The truth is, GLP-1 agonists alter your reward system,” said Dr. James J. Chao, co-founder and chief medical officer of VedaNu Wellness, who works with patients taking the drugs.

“When you drink, that warm, comforting glow you feel after knocking back a few might not happen,” he explained. “It could feel worse. It could feel like nothing at all.”

To understand why, it helps to know what these blockbuster obesity and diabetes treatments are doing inside the body.

GLP-1s work by mimicking hormones that your gut normally releases after eating. Those hormones help control blood sugar, regulate appetite and quiet cravings — which is why the drugs can be so effective for weight loss.

But they don’t just act on the stomach. They also affect the brain.

One key target is a tiny, pea-sized region known as the habenula, which plays a major role in how we experience reward, motivation and aversion.

“When the habenula is on, it causes all kinds of trouble, including cravings and withdrawal symptoms,” said Dr. Kyra Bobinet, a physician and behavioral neuroscience expert. “It really drives us to use.”

Drugs like Ozempic appear to dial that system down. When the medications reach the brain and bind to receptors in the habenula, they reduce the compulsive pull behind behaviors like overeating — often described by patients as “food noise.”

That’s one reason why GLP-1s are now being studied as potential tools for treating or preventing substance use disorders. Researchers suspect they may curb reward-seeking behavior and reduce cravings for people struggling with things like alcohol, nicotine and opioids — though we’re still quite a few years away from them being covered by insurance fort that purpose.

But the effects may not be limited to people with an addiction. Experts say even casual drinkers like Luker-Stewart may find their relationship with booze changing while taking GLP-1s.

“When the usual dopamine-driven euphoria is blunted, the emotional effects of alcohol can feel very different — more subdued, more introspective, or even dysphoric or ‘a sad drunk,’” said Dr. Fernando Ovalle Jr, a double board-certified plastic surgeon and obesity medicine specialist.

The medication may also explain why Luker-Stewart now pays a steeper price the morning after.

“GLP-1s slow gastric emptying, which changes how alcohol is absorbed,” Ovalle said. “That can make intoxication feel delayed, prolonged, and in some cases, people feel ‘off’ the next day.”

There’s also a basic but often overlooked factor: People on GLP-1s tend to eat and drink less.

“Alcohol consumed in a relatively dehydrated, under-fueled state, especially with low protein intake, will hit harder and produce worse hangovers,” Ovalle said. “That alone can explain severe next-day symptoms.”

And for many patients, their tolerance naturally drops along with the number on the scale.

“Some people weigh significantly less than when they started GLP-1s, which would contribute to a lower alcohol tolerance,” Chao noted.

At one point, Luker-Stewart stopped taking the weight loss medication for about six months, satisfied with the pounds he’d shed.

His appetite and cravings for food came roaring back — but his old experience with drinking didn’t.

“I expected the alcohol side effects to do the same thing as the food, but it didn’t really ever go away,” he said. “Am I bummed about it? A little bit, because I used to be a fun drunk. But it’s better for my health.”

Experts say there’s currently no strong evidence that GLP-1s permanently change how the body processes alcohol or alter users’ brain chemistry in the long term. But Bobinet suspects Luker-Stewart’s brain’s reward system may still have been adjusting.

“The habenula is an area of nerves that become calibrated to your lifestyle,” she said. “It might still be getting signals to be like how he was on a GLP-1.”

A Novo Nordisk spokesperson noted that there are “numerous studies” exploring the association between GLP-1 use and reductions in behaviors sometimes linked to addiction.

“GLP-1 receptor agonists are known to affect areas of the brain associated with controlling hunger and satiety and these are also home to the brain’s reward system,” the spokesperson said in a statement shared with The Post.

These days, Luker-Stewart takes a maintenance dose of tirzepatide about once a month to help sustain his weight loss. His lower tolerance for alcohol — and the rougher mornings that come with it — have stuck around.

“It definitely changed something in me,” he said.

Still, Luker-Stewart believes the trade-off has been worth it.

“I would not have lost 60 pounds any other way,” he said. “I’ve gone to the gym my whole life and nothing has given me the results that I received from a GLP-1, and ultimately, that’s what I was going for.”