Kendra Pierre-Louis: Filling in for Rachel Feltman, this is Kendra Pierre-Louis presenting Science Quickly from Scientific American.
In early March, the U.S. Food and Drug Administration issued a warning to Novo Nordisk, the manufacturer of Ozempic and Wegovy, for not revealing potential risks tied to these medications. The FDA claimed that Novo Nordisk did not adequately report or investigate three deaths linked to semaglutide, the main component in Ozempic and Wegovy.
These drugs belong to a class known as GLP-1s, which have gained significant popularity for uses ranging from type 2 diabetes management to weight loss. They are increasingly viewed as beneficial beyond these conditions. The surge in demand has resulted in numerous GLP-1 products flooding the market, many of which lack FDA approval.
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We interviewed Lauren Young, an associate editor specializing in health and medicine at Scientific American, to discuss the future of GLP-1s.
Pierre-Louis: Thank you for joining us, Lauren.
Lauren Young: Thank you for having me.
Pierre-Louis: Could you explain what a GLP-1 is?
Young: Certainly, GLP-1 drugs, often recognized from catchy ads, are sold as Wegovy and Ozempic, and contain the active ingredient semaglutide. You might also know Zepbound and Mounjaro, which contain tirzepatide. Originally designed for type 2 diabetes, these medications are now also used for weight loss. They work by mimicking the hormone glucagonlike peptide 1, or GLP-1.
This hormone triggers insulin production, making it effective for diabetes treatment. Researchers also discovered that these drugs reduce appetite, leading to eating less and losing weight, by affecting satiety levels. The drug essentially replicates the hormone’s function.
Pierre-Louis: I understand that GLP-1s in our bodies generally act briefly, but the drugs extend this duration?
Young: Exactly. Manufacturers have designed these drugs to remain active longer by resisting faster breakdown by body enzymes, maintaining activity for about a week.
Pierre-Louis: There’s been growing concern about imitation GLP-1s, like compounded versions. What is a compounded drug?
Young: Compounded drugs are made by compounding pharmacies to create customized medicines for individual needs. For example, if someone can’t take an oral medication, it might be converted into a cream or IV drip, or a lower dose for children. Animals might also receive compounded medications tailored to their specific needs.
Pierre-Louis: I once had a bespoke anti-inflammatory lotion for an ankle injury…
Young: Yeah.
Pierre-Louis: …prescribed by my doctor and made by a compounder.
Young: Exactly, that’s a perfect example. These compounded pharmacies fulfill important needs, but none of these drugs are FDA-approved, meaning they aren’t tested or reviewed for safety or effectiveness.
Pierre-Louis: What role have compounding pharmacies played with GLP-1s?
Young: Compounded GLP-1s gained prominence when these drugs became highly popular. Ozempic, often used off-label, spiked in use among celebrities, and semaglutide was approved for weight loss in 2021. This increased demand led to shortages in 2022, and tirzepatide, sold as Zepbound and Mounjaro, also faced shortages.
When shortages occur, compounders can produce these drugs to meet demand, filling an important gap.
Pierre-Louis: But even after shortages ended, compounders continued production, right?
Young: Yes, tirzepatide was removed from the shortage list in late 2024, followed by semaglutide in 2025. These drugs remain compounded if specific dosages are needed, as prefilled pens might not suit everyone. Additionally, companies add “additives” to create custom versions. These additives claim to aid muscle loss or reduce nausea and gastrointestinal side effects common with GLP-1s. However, these additives are not tested for safety or efficacy.
Pierre-Louis: What advantages do consumers find with compounders over official versions?
Young: Compounders often offer these drugs at lower prices than official versions because they source cheaper active ingredients. This cost advantage is significant, especially for those needing specific dosages not provided by standard pens.
Pierre-Louis: In February, Novo Nordisk sued Hims & Hers, a major seller of compounded versions, but later dropped the case. What led to this lawsuit?
Young: Novo Nordisk accused Hims & Hers of marketing compounded GLP-1s as primary options instead of their drugs. They also claimed these were “copycat” versions. Since Novo Nordisk and Eli Lilly’s drugs are patented, creating direct copies is prohibited, prompting the lawsuit.
Pierre-Louis: But the lawsuit was dropped?
Young: Yes, it was dropped last week.
Pierre-Louis: Ozempic, primarily a diabetes drug, and Wegovy, which shares semaglutide with Ozempic but in higher doses, were noted. Since Wegovy’s 2021 approval for weight loss, there’s been a surge in GLP-1s, including tirzepatide, liraglutide, and dulaglutide.
Young: [Laughs.] It’s like a game figuring out which names are real. [Laughs.]
Pierre-Louis: Over the last 15 to 20 years, these drugs have been valued for diabetes and weight loss. Research now suggests they could help with conditions like alcohol use disorder.
Young: Yes, numerous studies have explored GLP-1s in addiction treatment. Anecdotal reports emerged, with users observing changes in cravings—not only for food but also for behaviors like nail-biting or alcohol and nicotine use.
This prompted research in addiction, as scientists wondered if food reward pathways overlap with addiction pathways, suggesting potential new treatments.
Recently, a large study within the Veterans Affairs healthcare system collected data from over 600,000 veterans…
Pierre-Louis: Mm-hmm.
Young: …primarily older white males with type 2 diabetes. They examined various GLP-1 uses and found these drugs reduced the risk of developing substance use disorders.
The study covered disorders like cannabis, opioid, and alcohol use disorders. It also showed reductions in drug-related mortality, sometimes by as much as 50 percent, which is significant.
This is promising for addiction researchers. I spoke with a researcher studying opioid addiction treatments. She’s conducting trials on GLP-1s to see if they can complement existing treatments, which require opioid use to treat the disorder. There’s much to explore, but it’s an intriguing area.
Pierre-Louis: Are there other unexpected benefits of these drugs?
Young: Wegovy is approved for reducing cardiovascular risk, which is known. I’m particularly interested in reproductive health. GLP-1s might help reduce inflammation, potentially leading to treatments for various diseases. Many research avenues are opening up.
Pierre-Louis: However, these drugs are not without concerns.
Young: True, while GLP-1s have been around for decades, the long-term effects are unclear as more people use them. A recent analysis linked GLP-1s to increased risks of skeletal disorders like osteoporosis.
Pierre-Louis: Mm-hmm.
Young: There’s also concern about muscle or lean mass loss with GLP-1s. Weight loss through these drugs, exercise, diet, or malnutrition involves losing various “types” of weight. While losing fat, muscle and bone mass also decrease, which is crucial for older adults, many of whom have type 2 diabetes. These factors need consideration.
Another point is many users stop these drugs after about two years…
Pierre-Louis: Mm-hmm.
Young: …which seems to be the average. Studies are examining what happens to health benefits after stopping. For instance, improvements in cardiometabolic health revert quickly. A January study showed weight and health benefits bounce back faster after quitting a GLP-1 drug compared to exercise or diet.
Moreover, Rozalina McCoy, a University of Maryland researcher, noted that weight regained, especially after drug treatment, tends to be fat rather than muscle. This differs from physical exercise, where good habits may persist, or diet, where better eating patterns might remain. These are key concerns for researchers.
Finally, significant gastrointestinal side effects lead to many quitting after two years.
Pierre-Louis: It seems crucial to weigh pros and cons carefully, especially if using these drugs for weight loss, and consider long-term effects, given that users might not remain on them indefinitely.
Young: Yes, these drugs are marketed and prescribed as lifelong treatments. Questions about access and maintaining treatment remain, and long-term studies are needed. It’s an exciting area to cover in health.
Pierre-Louis: That concludes today’s discussion. Join us on Friday when associate books editor Bri Kane interviews Andy Weir, author of the sci-fi novel Project Hail Mary, with its Hollywood adaptation starring Ryan Gosling premiering Friday.
Science Quickly is produced by me, Kendra Pierre-Louis, alongside Fonda Mwangi, Sushmita Pathak, and Jeff DelViscio. This episode was edited by Alex Sugiura. Shayna Posses and Aaron Shattuck fact-check our show. Our theme music is by Dominic Smith. Subscribe to Scientific American for the latest in-depth science news.
For Scientific American, this is Kendra Pierre-Louis. Have a wonderful week!
