A look at how Ozempic works for weight loss and the problems it may create

Some people who've tried to lose extra weight for years are finally slimming down thanks to the newest generation of weight loss drugs.

One such weight loss patient, Lisa, heads into her monthly checkup at Dr. Ian Yip's Woodland hills office. 

After her weigh-in, Dr. Yip checks her vital signs. Noticing that her blood pressure is within a very good range, Yip remarks at the good news: Lisa has lost 70 pounds.

"People have always said 'Oh you're so pretty, but like you need to lose weight,'" Lisa said. 

As her weight went up, Lisa's activity level went down. When she turned 30, she said a flight of stairs could leave her breathless.

"It did affect my self-esteem," she said. 

After trying to lose weight on her own, Lisa underwent lap band surgery in 2012. While she initially lost the weight, two years later, the pounds came back. 

Lisa isn't the only one with this problem. 

Yip once ran the bariatric surgery program at UCLA. He and his colleagues found that patients would eat more often when their stomachs were restricted. This finding indicated that the drive to eat was just as present in the brain as in the stomach, meaning that hormones appeared at the wheel. 

"I have quite a lot of patients with weight regain after the surgery would come back in and start using these medications," Yip said.

Earlier this year, talk show host Oprah Winfrey gave a voice to Americans struggling with weight and their decision to lean on injectable medications. She previously acknowledged she has used medication, though she never specified which one.

Celebrities like Kelly Clarkson, Tori Spelling, Sharon Osbourne and Elon Musk have also acknowledged leaning on medical help. 

The best-known drug used by some is Ozempic, which has an active ingredient called semaglutide. It mimics a natural hormone. 

"We call it GLP-1," Yip said. "This hormone comes out naturally when we eat."

Yip explained that GLP-1 instructs the pancreas to make more insulin and slows down the movement of food through the gastrointestinal tract.

"It makes you feel full," he said. "You will feel like you ate a big meal even when you have a tiny portion of it."

However, this could cause vomiting and diarrhea. Manufacturers recommend an "initiation dose for new patients to combat side effects. 

"The highest dose is ten times stronger than the starting dose," Yip said. "Every month, you see how they're doing."

While Ozempic and another drug, Wegovy, contain the same ingredient — semaglutide — the Food and Drug Administration approved them for different uses. Ozempic should be used to treat diabetes while Wegovy should be used to treat obesity. 

For some people, the side effects become overwhelming before the dose gets high enough to reach their weight-loss goal. 

This created a demand for a newer compound called tirzepatide, the active ingredient in Mounjaro and Zepbound. The former is approved for diabetes, while the latter is approved for obesity.

"They bind to two receptors," Yip said. "The second receptor makes the patient tolerable to the higher dosage of the medication to cause more weight loss."

Lisa started taking tirzepatide in 2022. As her dose went up, she experienced nausea and vomiting but it subsided after a month. 

"Now, I don't have any side effects at all, really," she said. 

Yip said patients who take these medications need medical monitoring. In lawsuits filed against the manufacturers, patients alleged that these medications have resulted in life-threatening intestinal blockages and thyroid cancer where there's a family history of gastroparesis or endocrine cancer syndrome. 

Lisa is on a maintenance dose of Zepbound and now easily climbs stairs. Yip said many patients need to be on the medication long-term. 

Increasingly, obesity is being viewed as a chronic condition, which means for some people, control could mean a lifetime of treatment.