Doctors are prescribing the weight loss drug semaglutide. Here's what you need to know, according to experts and people who have tried it.

A close-up of a medical syringe in a vial.
Semaglutide, also known by the brand names Ozempic and Wegovy, is quickly becoming a popular weight-loss medication. (Getty Images)

Like nearly 50% of Americans, Talia (not her real name) had gained weight over the pandemic and wanted to do something about it. After a friend lost 40 pounds using semaglutide — a prescription injectable weight-loss medication that’s garnering a lot of buzz right now — her interest was piqued.

The New York resident made an appointment with her friend’s doctor and asked about any potential risks and whether she needed to follow a specific diet while on the medication. “I was told that in clinical trials, participants lost an average of 15% to 20% of their body weight without adhering to a special diet,” Talia tells Yahoo Life. She adds: “It sounded like it was worth trying, so I decided to move forward.”

Talia started the once-weekly injections of semaglutide (also known by the brand names Ozempic and Wegovy) in July 2021 and began losing around 4 to 5 pounds per month. “I think around Christmas, I noticed a change in my face — where I tend to carry weight — and after the Christmas holiday, my co-workers started commenting on my appearance,” she says.

She eventually lost 50 pounds, reaching the significant weight-loss goal she’d set for herself. “I am very happy with the results,” Talia says. “I had hoped to reach the goal sooner, but I do not exercise, so I expect that slowed the process a bit.”

Vanessa (last name withheld) heard about semaglutide from a medical practice she works with, after the owner lost 30 pounds in five months on the medication. Impressed with her results, Vanessa decided to try it herself. “It seemed like a healthier way to go about weight loss versus eating frozen processed foods, counting calories, etc.,” the Washington resident tells Yahoo Life.

Although she already exercises regularly and eats healthfully, Vanessa has made some lifestyle changes since starting semaglutide. “I would say that the biggest changes I made were eating more proteins, drinking more water — and adding electrolytes to my water — and eating more greens,” she says. “My body actually really craved that. It also forced me to eat smaller portions, as semaglutide sort of tricks your brain into feeling full, and you aren’t craving sugar.”

She also found herself less interested in drinking alcohol. “My body sort of rejects it after one to two drinks,” Vanessa says. “It’s the strangest thing, but I am not complaining!”

Within two months, she had lost 10 pounds. Now, in her 11th week, she is down 14 pounds. “I am very pleased,” Vanessa says.

It’s hard to read about results like these — all achieved without highly restrictive eating plans and punishing workout routines, the usual hallmarks of diets that promise significant weight loss — and not view semaglutide as some sort of magic bullet.

But how does semaglutide help with weight loss? Is it safe? And does it actually keep the weight off? Here’s what you need to know, according to experts.

First, how does semaglutide help with weight loss?

Semaglutide was developed as a medication for type 2 diabetes, garnering FDA approval in 2017. However, clinical trials and post-marketing surveys “clearly demonstrated that the drug also has the capability of helping people lose weight,” Dr. Zhaoping Li, chief of clinical nutrition and professor of medicine at UCLA Health, tells Yahoo Life.

In February 2021, the FDA approved semaglutide for chronic weight management in adults who are obese or overweight and have at least one weight-related health condition, such as high blood pressure, type 2 diabetes or high cholesterol. Before that, it had been seven years since the FDA approved a drug for chronic weight management. Currently, that small list of approved prescription medications includes drugs such as orlistat (Xenical), liraglutide (Saxenda), bupropion-naltrexone (Contrave) and phentermine-topiramate (Qsymia), according to the Mayo Clinic.

Dr. Claudia Ramirez Bustamante, fellow physician of medicine-endocrinology at Baylor College of Medicine, tells Yahoo Life that semaglutide is “very effective” for weight loss. A 2021 study on semaglutide in the New England Journal of Medicine found a 15% reduction in body weight, while Bustamante points to a 2022 extension of the original study, which shows that participants lost an average of more than 17% of their body weight while on 2.4 mg of the medication. For a 175-pound person, for example, 17% is a loss of nearly 30 pounds.

Given that people on other prescription weight-loss medications lose, on average, 3% to 12% of their body weight after a year, it’s not surprising that semaglutide’s results are leading some experts to call the medication a “game changer.” As Li puts it: “It’s great to add another tool to our toolbox.”

So how does it work? Semaglutide helps control blood sugar by stimulating insulin secretion, while protecting against cardiovascular problems. The medication also causes a “minor delay” in gastric emptying, which contributes to people feeling fuller longer and therefore eating less.

“Semaglutide slows gastric emptying, thus making the absorption of nutrients slower in the gut,” explains Bustamante. “In addition, it acts in the areas of the brain involved in appetite regulation. In practical terms, patients taking semaglutide have decreased appetite and feel satiated with smaller portions, which lead to weight loss.”

What are the side effects?

The medication is not without its downsides. The main side effects of semaglutide are abdominal pain, bloating, nausea, vomiting, diarrhea or constipation, explains Bustamante. But they’re temporary. “Usually, these side effects tend to wear off after one to two weeks,” she says. “However, in some patients they can persist and warrant dose adjustments and, if severe, discontinuation of therapy.”

Vanessa shares that she experienced “nausea, gas pains and fatigue initially” but adds that once the side effects “calmed down, it was a pretty seamless way to lose weight.”

Your bank account, however, may also suffer some side effects. That’s because the cost of the drug is “substantial,” says Li — about $1,300 per month for four shots. “There is also insurance coverage issues for weight loss,” she says, referring to the fact that the pricey drug may not be covered.

It’s not clear why insurance doesn’t always cover semaglutide for weight loss if it’s FDA approved, but several factors may be at play. One possible reason may be the sheer volume of the potential patient population who might seek coverage, given that nearly 1 in 3 adults in the U.S. is overweight and more than 2 in 5 adults have obesity, according to the National Institute of Diabetes and Digestive and Kidney Diseases. Another reason may be that insurance companies have had “plenty of lessons learned from multiple drugs that had to be withdrawn from market despite their efficacies,” Li says, pointing out, for example, the once popular weight-loss drug combination fenfluramine-phentermine, known as fen-phen, which was also viewed as a “miracle” but was pulled off the market in 1997 for causing heart valve damage.

Are there any risks?

Yes, say experts. “There is a risk of progression of diabetic retinopathy,” says Bustamante, referring to a diabetes complication caused by damage to the blood vessels at the back of the eye. “There is also a risk of acute pancreatitis. Thus, this medication would be precluded in patients with chronic pancreatitis or pancreatic neoplasia [pancreatic cancer].”

Semaglutide is not recommended for people with a personal or family history of thyroid cancer (in particular, medullary thyroid cancer) because the medication may increase the risk for that, according to Li.

Does the weight come back after stopping the medication?

Both Talia and Vanessa have some concerns about how stopping the medication will affect their weight. “I do wonder what will happen when I stop taking the injections, and worry that if I do, the weight may come back,” says Talia.

That’s a legitimate concern given that research shows people who lost weight on 2.4 mg of semaglutide regained two-thirds of the weight they’d lost within a year of stopping the drug, “suggesting that this medication should be taken indefinitely to maintain weight control,” says Bustamante.

For Vanessa, she says that knowing there is a “maintenance program” helps, and “I do think it weans you off in a good way.” She adds: “The idea is to have changed various habits and stick with that. I am committed to keeping it off, and that is half the battle with weight loss programs.”

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