What You Need to Know About New Weight Loss Drugs
Are Ozempic, Wegovy and other approved drugs safe and effective for older adults?
Ozempic, Wegovy, Mounjaro and Zepbound are all Food and Drug Administration-approved drugs many people use for weight loss, but we wondered whether there are any safety concerns or side effects for people over age 50. We also wanted to know if the drugs are as effective for weight loss in menopausal and postmenopausal women as they are for men and younger women. We scoured the research and talked with experts to find out.
Glucagon-like peptide-1 receptor agonists (GLP-1s for short) are a class of medications that millions of people are currently using to lose weight and manage type 2 diabetes (T2D).
GLP-1 agonists have been around since 2005, but it's the most recent iterations such as semaglutide (Ozempic and Wegovy) and tirzepatide (Mounjaro and Zepbound) that you've likely been reading about in the news. That's because subjects in recent clinical trials have lost much more weight on these novel drugs than on previous versions of GLP-1 agonists.
"These medications aren't a magic wand. They need to be used as part of a holistic approach to how you live your life."
To learn more about them, we spoke with Alexandra Sowa, M.D., an internist and obesity medicine specialist who is the physician founder of SoWell Health and the author of the forthcoming book, "The Ozempic Revolution" (HarperCollins, February 2025).
Sowa explains, "GLP-1 medications are mimicking a hormone called GLP-1 that occurs naturally in the body. They help us lose weight by communicating with the brain, gut and pancreas. This helps us consume less, but it also rebalances hormones by stabilizing blood sugar, resulting in weight loss."
While GLP-1 agonist use has skyrocketed, not just anyone can take them. For starters, Ozempic and Mounjaro are FDA-approved only to treat overweight and obese individuals with T2D. Wegovy and Zepbound are approved to treat obesity and weight in individuals without diabetes.
In both cases the FDA regulation stipulates that an individual must have a BMI of 30 or more with no other co-morbidities (such as high blood pressure, high cholesterol or T2D) or a BMI of 27 or higher with at least one co-morbidity.
Beyond the regulatory restrictions, Sowa stressed that these drugs are for individuals who have tried incorporating healthy lifestyle habits, but weren't able to reach a healthy weight through that alone. "These medications aren't a magic wand," she says. "They need to be used as part of a holistic approach to how you live your life."
That was the case for Heather Mullane, a 48-year-old air traffic operations manager in Minneapolis. "My weight peaked in early 2023 and I worked really hard over the next few months and lost about 35 pounds on my own through healthy diet and exercise," she says in a phone interview. But after that, Mullane hit a plateau, and no matter how strictly she adhered to her regimen, the scale wouldn't budge.
"What makes me the happiest is that now my body reflects all of the work that I do."
She was about to give up, but instead booked an appointment at a medical center specializing in weight loss. She worked with a dietician for several weeks, but progress was still negligible. Eventually, she saw a nurse practitioner who prescribed the lowest dose of Wegovy for her.
Over the next several months, Mullane's care team slowly increased the dosage of the once-weekly injections from 0.25 milligrams to 0.5 mg and then 1.0 mg. Between December 2023 and April 2024, her BMI dropped from 32 to 29. "What makes me the happiest," Mullane says, "is that now my body reflects all of the work that I do."
Mullane's experience is typical of many who take the new GLP-1 agonists. In a sweeping review of the clinical trials to date, a July 2024 paper published in the American Journal of Cardiology found that over 85% of subjects taking once-weekly injections of the full dosage (2.4 mg) of semaglutide lost more than 5% of their body weight, with over one-third of participants losing more than 20%.
"Versus other weight loss methods, women tend to do better and lose more weight [on GLP-1 agonists] than men."
These drugs particularly offer hope for women who often have a tougher time losing weight than men, especially during and after menopause. "Actually," Sowa says, "versus other weight loss methods, women tend to do better and lose more weight [on GLP-1 agonists] than men, which is great, because we don't generally see that." She adds, "We don't have data yet that's just focused on the post-menopause population, but anecdotally it's been really effective."
In the American Journal of Cardiology review cited above, more than 75% of participants were women, and the mean age of each trial was between 46 and 51.
Risks and Side Effects
With results like that, it's easy to understand the drugs' popularity. But, as with any medication, the risks of side effects are real. Another huge factor to consider is that once someone starts taking a GLP-1 agonist, they should stay on it forever.
"People need to know that this is for life," Mullane says. That's one reason why she and her care team decided to stay at the lower dose, rather than increasing it to the standard 2.4 mg per week. That lower dosage also helps her manage the most common side effects of the drug, which include nausea, constipation, diarrhea and vomiting. More than three-fourths of the participants in the studies reviewed experienced those symptoms, though only 3% dropped out due to symptom severity.
"I feel like if I had been on the full dose from the beginning, I would have gotten way too skinny and been miserable," Mullane says. Now, she says, "I get a little nauseated on the days I inject," and she has to be careful about eating fatty foods in order to avoid diarrhea.
"The big concern for people over 50 is retaining muscle. I call this a side effect."
More serious side effects, while rare, are possible. The International Journal of Molecular Science published a paper discussing a possible link to a specific type of thyroid cancer in April 2024, and the FDA is monitoring reports of suicidal thoughts or actions by those taking the drugs. While the current research in both cases has shown no direct causal relationship, professionals in the research, medical and regulatory communities all agree these drugs should only be taken at the direction and under the care of a medical professional.
Sowa has an additional concern, particularly for people over 50. "These drugs are not for thinness, they're for health," she cautions. "The big concern for people over 50 is retaining muscle. I call this a side effect. The drugs don't make you lose muscle, but they make you lose more weight than if you were on a low-calorie diet alone."
That's why, she says, it's imperative for people over 50 who are taking the drugs to eat adequate amounts of healthy protein and incorporate strength training into their exercise regimen.
Supply Shortages and Copies
Even for those who meet the requirements to get a prescription for one of the new drugs, obtaining that first dose is not guaranteed.
Due to high demand, both semaglutide and tirzepatide injections have been on the FDA's drug shortage list since 2022. As National Public Radio recently reported, this can make the drug difficult or impossible to get at times.
For many who can find the drug at their required dosage, their insurance provider won't cover the cost, which currently ranges from $900 to $1,600 per month. "Insurers at this point have the option to cover it or not," Sowa says, adding that most state-held insurers aren't covering the drugs but many private insurers are. "This is a problem, because obesity is a disease, and it's the root cause of many other diseases."
Both of these issues have helped spur sales of copy-cat versions of the drugs. Representatives from the FDA's Office of Media Relations explain that because of the shortage of the brand-name drugs, pharmacies are authorized to produce compounded drugs, which are "essentially copies of commercially available drugs."
"When there is less regulation of something you're injecting into your body, you need to be careful."
The fact that those drugs can be manufactured and sold legally, however, does not mean they have been tested and approved by the FDA.
Sowa sums up the situation: "Compounding pharmacies can be a wonderful resource, but overall the process of making products like this is not FDA regulated. When there is less regulation of something you're injecting into your body, you need to be careful."
Chanapa Tantibanchachai, a spokesperson for the FDA, also stresses that a prescription is still required for compounded drugs. "If someone is not asking you for a prescription, that is a major, major red flag and you shouldn't be taking it."
The best practice for anyone considering these new weight loss drugs is to seek guidance from a credible, impartial doctor or nurse practitioner specializing in weight management.
