Ozempic is a medication that helps people with type 2 diabetes regulate their blood sugar levels. One of its most significant side effects is weight loss, which explains why it has become wildly popular for non-diabetics looking to slim down. However, shedding those extra pounds is far from the only side effect of Ozempic. So, before rushing to buy Ozempic as a weight-loss solution, it is essential to know what you are getting into.

In this article, we detail and explain side effects related to Ozempic in order to help you make an informed decision about the drug in the best interests of your health. As Ozempic is still so new, some of these side effects are medically proven while others are only based on anecdotal reports.

Let’s start by looking at common and relatively minor side effects before turning to its rarer but potentially much more serious side effects.

Relatively common and minor side effects

The most commonly reported and relatively minor side effects of Ozempic are as follows:

Gastrointestinal problems: diarrhea, constipation, abdominal pain, nausea, and vomiting

Gastrointestinal issues are by far the most commonly mentioned negative side effect reported by Ozempic users. Although most users don’t report these problems, a significant minority do. For some people, the gastrointestinal issues are major enough to stop them from taking the drug altogether.

Studies reported on by the U.S. Food and Drug Administration (FDA) have identified the likelihood of users taking one milligram of Ozempic’s active ingredient semaglutide experiencing various gastrointestinal issues.

According to their data, the most common such issue was nausea, which was reported by 20.3% of participants in the trial. That was followed by vomiting (9.2%), diarrhea (8.8%), abdominal pains (5.7%), and constipation (3.1%). A smaller percentage of patients reported experiencing acid reflux, flatulence, or excessive belching. Anecdotal evidence suggests some users experience particularly foul-smelling, eggy burps as a result of taking Ozempic.

It should be noted that the percentages above are based on users taking 1 milligram of the drug. However, the recommended initial dose is 0.25 milligrams (rising to 0.5 milligrams after four weeks). It appears that patients following those recommended doses are less likely to experience gastrointestinal problems as another source suggests that less than 5% of all users encounter such issues when taking Ozempic.

The flip side of that is that non-diabetic users who are taking the full 2.4 milligrams of semaglutide are much more likely to face gastrointestinal issues. One trial reported in the New England Journal of Medicine of Ozempic’s sister drug Wegovy (which contains a 2.4-milligram dose) found that 44.2% of users experienced nausea, 31.5% diarrhea, 24.8% vomiting, 23.4% constipation, 10.0% abdominal pain, and 9% belching. In total, 74% of users in the trial had at least one gastrointestinal problem while taking the drug.

Anecdotal evidence suggests that gastrointestinal issues are most likely to manifest closest to the times when you inject the drug (which is designed to be taken once per week). Such problems are also more common in new users of the drug and in people who increase their regular dosage. The same evidence also suggests that the problems tend to go away over time as the user’s body becomes accustomed to Ozempic.

Flabbiness and muscle loss

Since the start of 2023, social media has been filled with anecdotal reports of conditions that have come to be known as “Ozempic face” and “Ozempic butt.” The terms, which have made headlines around the world, refer to the flabbiness around the cheeks and buttocks.

However, this particular side-effect appears to be nothing special to worry about. Weight loss, especially rapid weight loss, always comes with a risk of leaving behind some flabby skin—it’s just one of the potential natural consequences of losing fat that dieters have always had to face. So, while Ozempic might leave some flabbiness around your face, buttocks, or elsewhere, the same risk exists with any weight-loss solution, especially one that acts rapidly.

When it comes to muscle loss, again some is to be expected as a natural part of any weight-loss regime. However, some physicians, such as Peter Attia MD, have raised concerns that the amount of muscle loss associated with drugs containing semaglutide is surprisingly high and unhealthy. Dr. Attia has argued that the amount of muscle that Ozempic users are losing relative to fat should make anyone thinking about using the drug for weight loss “exercise extreme caution.”

Evidence from analyses of the body compositions of semaglutide users appears to back up some of his concerns, with trials showing that dieters using Ozempic’s active ingredient lost around 60% fat and 40% lean mass. In contrast, dieters using more conventional methods only lose 20–30% lean mass. Although it is not yet proven that Ozempic causes unhealthy levels of muscle loss, users would still be well-advised to combine taking the drug with an exercise regime designed to build muscle.

Hair loss

Anecdotal evidence is increasingly suggesting that weight might not be the only thing that Ozempic users are losing, with reports coming in that some are shedding hair too.

Indeed, although Ozempic does not list hair loss as one of its potential side effects, it probably should. That’s because Wegovy, Ozempic’s sister drug, does list hair loss as one of its potential side effects. The risk of hair loss is not huge (3% of participants in trials of Wegovy reported some shedding of hair), but it is still significant enough to be mentioned.

However, just as with the facial flabbiness mentioned above, hair loss can be a natural consequence of weight loss however you achieve it. Again, that is especially the case for people going on crash diets to lose weight rapidly, which is just what people taking Ozempic are trying to achieve.

Dizziness and fatigue

A small minority of people taking Ozempic have reported episodes of dizziness associated with their drug use. There is a possibility that such episodes stem from the fact that the drug lowers glucose levels, which can cause dizziness.

Over 10% of participants in a trial of Ozempic’s sister drug Wegovy reported feeling fatigued, i.e., a sense of tiredness that does not go away after sleep. It’s important to be aware of this potential side effect, but it is possible that it simply stems from the fact that Ozempic users eat much less food; without your usual fuel, it is no surprise that you might become fatigued.

Other relatively minor side effects

Other relatively minor potential side effects of Ozempic include the following:

  • Increased heart rate: the FDA has reported that low doses of Ozempic can increase heart rate by an average of two to three beats per minute. Patients who experience significant heart rate increases should stop taking Ozempic.
  • Reduction in addictive and compulsive behavior: a reminder that not all side effects are necessarily bad. Reports that Ozempic users are less likely to compulsively gamble, drink, shop, and pick their nails have led The Atlantic to ask, “Did scientists accidentally invent an anti-addiction drug?
  • Ozempic dreams: this refers to the apparent tendency of users to experience vivid and unusual dreams that often involve celebrities. This side effect was reported in The Wall Street Journal, but any evidence for it is strictly anecdotal.

Rarer and more serious side effects

Taking Ozempic has also been connected to the following uncommon but extremely serious side effects:

  • Allergic reactions: serious allergic reactions to Ozempic are very rare but require immediate, emergency medical attention
  • Eyesight problems: diabetics taking Ozempic may be at greater risk of developing diabetic retinopathy, a serious condition that can cause blindness, according to a large-scale study on the subject. A similar study, however, concluded that there was no increase in risk.
  • Hypoglycemia: Ozempic’s glucose-lowering effect can increase the risk of hypoglycemia, meaning that diabetics should be extra careful about checking their blood sugar levels and the sizes of their insulin doses when also taking Ozempic.
  • Kidney failure: there are recorded instances of the use of Ozempic’s active ingredient semaglutide causing kidney disease. This risk is exacerbated by the potential dehydrating side effects of Ozempic, such as vomiting.
  • Pancreatitis: a potentially life-threatening condition in which the pancreas comes under attack from digestive enzymes; it often manifests in a strong pain in the stomach that spreads to the back.
  • Gallbladder disease: infection, inflammation, or blockage of the gallbladder that can manifest in serious stomach pain, clay-colored stools, and yellow eyes or skin.
  • Thyroid tumors/cancer: these have been found in studies of rodents being dosed with the active ingredient of Ozempic, but it is not yet known if the drug can cause thyroid cancer in humans.

Conclusion

As we have seen, taking Ozempic for weight loss can potentially create a whole host of unwanted side effects, which range from relatively common and minor to much rarer but potentially extremely serious. Evidence for the side effects comes from sources including both solid clinical trials and anecdotal evidence on the internet. Nevertheless, even the anecdotal evidence should not be dismissed altogether.

Any users of Ozempic would be wise to be aware of all potential side effects so that they can do their research thoroughly and make a fully informed decision about what they are getting into. It’s also worth remembering that doctors have pointed out that because Ozempic is still such a new drug it might have lots of other unintended health consequences that have not yet been identified.

All of these potential side effects strengthen the argument that taking Ozempic should be reserved only for those who have a pressing medical reason to do so. Anyone contemplating using the drug should certainly consider taking professional medical advice first. If you do start to take it and experience any adverse reactions, please consult a registered healthcare provider.