The unintended side effects of popular weight loss drugs
Know what you're in for before taking the risk.
You’ve probably heard a lot about Ozempic and Wegovy, the semaglutide wonder drugs for weight loss. Their newfound popularity with prescribers and online pharmacies has sparked a global shortage. Other diabetes medications are now also being repurposed for weight loss: On Wednesday, the FDA approved Zepbound, another version of Mounjaro, for chronic weight management.
While Ozempic and Wegovy have different ingredients than Mounjaro and Zepbound, they work in a similar way. Semaglutide mimics a hormone called GLP-1 that’s usually released when the body detects carbohydrates, proteins, and other lipids after a meal. This sends a message to the brain that you’ve eaten, changing hunger signaling activity. When the body thinks it’s full, GLP-1 activates other systems to slow down muscle contractions that would usually move food out of the stomach.
A weekly injection might seem like an easy option to shed pounds, but doctors warn these medications are not a perfect weight-loss solution. Semaglutide carries a number of side effects that range from uncomfortable to life-threatening, which can be even worse with off-label use of Wegovy or Ozempic.
What are the common side effects of semaglutide?
Since semaglutide has a direct effect on the GI tract, a majority of the side effects are gastrointestinal-related. Mir Ali, a bariatric surgeon and medical director of MemorialCare Surgical Weight Loss Center in California, says about 50 percent of people taking Wegovy or Ozempic experience nausea. Other common side effects include constipation, diarrhea, or cramping. People who overeat while on the regimen might experience more severe nausea and even vomiting. Additionally, while not as common as the other GI side effects, Ali mentions there is a chance of dizziness while taking Ozempic. This may stem from the blood sugar-lowering effects of the drug.
“These symptoms tend to go away with time as the patients continue their medications. The body adapts to [the drug],” says Ali. He adds that people prescribed Ozempic or Wegovy often start off on a lower dose and eventually work their way up to avoid jarring side effects.
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If you experience nausea, Ozempic’s makers advise eating more slowly and switching to bland, low-fat foods such as crackers and plain toast. People should also eat soups and gelatin, which contain high amounts of water. After meals, drink ice-cold water and avoid lying down.
What are the more dangerous side effects?
Since large numbers of people started using semaglutide for off-label weight loss, doctors have been documenting more troubling reactions. New research published in the Journal of the American Medical Association links Ozempic to gastroparesis, a chronic condition that severely weakens the muscles in the stomach wall, making it harder to push food over to the small intestine. The inability to empty stomach contents can delay the digestive process and induce regular episodes of nausea and diarrhea. While there are surgical and non-surgical ways to manage gastroparesis, there’s currently no cure for it.
Considering that there have only been a few documented cases of gastroparesis with Ozempic use, Ali says the chances of this happening are relatively rare and “not something you typically see in patients.” But as demand for the drug continues to soar, more cases may come to light. Along with stomach paralysis, other limited but severe side effects of Ozempic involve pancreatitis, kidney issues, and gallbladder issues.
Can semaglutide cause suicidal thoughts?
A growing number of people worldwide have also reported suicidal thoughts while taking Ozempic. After receiving 150 reports of suicidal ideation and self-injury, the European Medicines Agency is reviewing the safety data on the diabetes drug. The United Kingdom is also reviewing all drugs classified as GLP-1 agonists, including Ozempic, after an uptick in incidences of self-harming thoughts. In the US, individuals have spoken out about experiencing suicidal ideation while taking Ozempic, despite having no history of self-harm.
Overall, cases of suicidal ideations are largely anecdotal and relatively rare.
Some of the mental health concerns have precedent. The US Food and Drug Administration (FDA) requires any chronic weight management medication that works on the central nervous system to carry a warning about suicidal behavior and ideation. Wegovy has a warning for suicidal ideation but Ozempic—intended only to control blood sugar levels in people with type 2 diabetes—does not. It’s not clear what the link is between these drugs and suicidal thoughts, but it’s assumed the neuropsychiatric side effects emerge when semaglutide interacts with the brain to control appetite.
“The question becomes, should the same medication under a different name carry the same caution regarding suicidal ideation?” says Joseph Barrera, an endocrinologist and associate medical director of Providence Mission Hospital in California. He adds that the likelihood of developing self-harming thoughts while taking Ozempic seems to occur more in people with a history of depression or other psychological issues—a possible safety concern as some psychiatrists are now prescribing Ozempic for depression.
Overall, cases of suicidal ideations are largely anecdotal and relatively rare. As of September 2023, of the 23,845 reports of adverse reactions with semaglutide in the US, there have been 144 cases of suicidal ideation and 2 deaths by suicide. As Barrera points out, it’s still unclear how many of these cases involved Ozempic versus Wegovy.
What to consider if taking Ozempic or Wegovy for weight loss
Barrera has one piece of advice for people considering using Ozempic or Wegovy off-label: Don’t. The risks of taking the drug, including suicidal ideation, are too high. What’s more, Barrera warns some individuals have been paying providers and clinics for “compounded semaglutide,” which involves mixing multiple medications together. According to the FDA, people making compounded semaglutide are using a salt form, such as semaglutide sodium or semaglutide acetate, that doesn’t contain the same active ingredient as Ozempic and Wegovy.
Another factor to consider is affordability, as insurance companies are unlikely to pay for off-label use of either drug. Ozempic requires weekly shots and can cost about $900 per injection without coverage. It’s also designed to be taken long-term, so skipping out on the drug for even a week can cause food cravings and a rebound in weight.
Overall, semaglutide can be helpful in managing weight and improving your health if you’ve been diagnosed with a chronic condition. “It’s another tool to help with living a healthy lifestyle, and like any other tool, it works well if used properly,” says Ali. He advises people using weight loss drugs to think of it as a supplement, not a replacement to diet and exercise. Without combining the two, people will not see much of the desired results, he adds. “They are better medications than we’ve had previously, but nothing is perfect.”