weight loss · Jun 27, 2025

9 Lesser-Known Side Effects of Ozempic You Shouldn’t Ignore

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Written by Emily Johnson, MS, RD

Ozempic has become a household name, celebrated for its remarkable weight loss results. Many people have also heard that Ozempic comes with some side effects, like nausea and fatigue. But as more people start to use this drug, a collection of lesser-known side effects has emerged, frequently leaving people shocked and concerned. From unexpected hair loss to subtle mood changes, these lesser-known effects are important to be aware of if you’re taking the drug.

Ozempic, a semaglutide that belongs to a class of drugs called GLP-1 receptor agonists, can be an effective tool for managing blood sugar and supporting weight loss goals. But, like any medicine, it’s important to understand its complete risk profile. Some of these overlooked side effects may resolve when treatment stops, but others can lead to lasting health consequences. Recognizing these potential complications early, especially for non-diabetic users, allows you to have meaningful discussions with your healthcare clinicians about what’s best for you, your lifestyle, and your long-term health.

Common Side Effects of Semaglutide (Ozempic, Wegovy)

Most people starting semaglutide are prepared for the common gastrointestinal side effects that affect the majority of users during the initial weeks of treatment:

Nausea: Often the most prominent early symptom, typically occurring within hours of injection and gradually improving as the body adjusts to the medication.
Constipation: Semaglutide slows gastric emptying, which can lead to infrequent bowel movements that sometimes require dietary adjustments or over-the-counter remedies.
Vomiting: More severe than nausea alone, this can lead to dehydration and electrolyte imbalances if persistent.
Bloating: Uncomfortable abdominal distension can make clothing feel tight and interfere with daily activities.
Abdominal pain: Ranging from mild cramping to more intense stomach pain, this is often related to the medication's effect on digestive processes.
Diarrhea: Less common than constipation but equally disruptive, sometimes alternating with periods of constipation.
Fatigue: General tiredness and reduced energy levels may result from your body's adjustment to the medication.

While these familiar side effects are well-documented and often manageable with time and proper medical guidance, they’re only part of the semaglutide story [1]. Beyond these expected reactions lies a range of lesser-known effects that can have more serious implications for long-term health and well-being.

1. Bone Loss

Having strong bones helps us maintain our strength and functionality as we age. Weight loss, especially rapid weight loss, is linked to loss of bone density, which can put us at risk for complications with mobility and increase the risk of fractures [2].

When taking semaglutide, the often rapid weight loss people experience can increase the risk of bone loss. One study evaluated four separate groups of participants: a placebo group, an exercise group, a semaglutide group, and a group taking semaglutide and following an exercise program [3]. In all groups, the researchers also measured bone mineral density to assess bone strength.

The results found that the exercise group and those taking semaglutide lost the most weight and maintained their bone density compared to the placebo group. However, people who took semaglutide alone experienced some bone density loss compared to those who only exercised.

Takeaway: If you are taking semaglutide, it’s important to maintain a consistent exercise routine to prevent bone loss. Specifically, it’s important to incorporate strength training 2-3 times a week, as strength training has been linked to improved bone density in younger and older populations [4, 5].

2. Muscle Loss

When you lose weight, your body primarily sheds fat mass, but it is likely you will lose some muscle mass, too. In the case of rapid weight loss, which is common with Ozempic and similar semaglutides, your risk of muscle loss increases [6].

Over time, this can lead to sarcopenia, a condition that stems from the loss of essential muscle mass and presents mobility, metabolic, and weight-related problems as we age [7].

A meta-analysis of the effects of semaglutide on lean mass revealed that while participants lost a significant amount of fat mass, up to 40% of their total weight loss was attributed to muscle loss [8]. Notably, larger studies showed a greater degree of muscle loss than smaller ones. This shows that while semaglutide is good for fat loss, there is a significant risk of muscle loss to take into account.

Takeaway: To prevent muscle loss when losing fat mass, increase your intake of lean protein and incorporate strength training 2-3 times a week. Research shows that these can preserve lean body mass and prevent sarcopenia.

3. “Ozempic Face”

“Ozempic face” is a term that has been coined recently with the spike in widespread use of semaglutide. It refers to the loss of facial fat that occurs with rapid weight loss, and is characterized by gauntness, sunken eyes, and increased loose skin around the face and neck.

While this is a colloquial term rather than a scientific one, doctors say it is common with rapid weight loss [9]. While the speed of weight loss on semaglutide can’t be controlled, there are some things you can do to prevent “Ozempic face,” including hydration and dietary modifications. Also, if you stop taking the drug and gain weight again, your face may appear fuller and lose some of the gauntness due to increased fat.

Takeaway: Rapid weight loss can lead to changes in your face, but drinking 1-2 L of water a day, wearing sunscreen daily, and eating healthy fats and lean proteins (like avocado, nuts, seeds, and fatty fish) can help mitigate this side effect. You can also talk with your doctor about reducing the dosage of medication or switching your brand of semaglutide to slow weight loss.

4. Rebound Weight Gain

While semaglutides like Ozempic are known for how quickly and effectively they facilitate weight loss, what happens when you reach your goal weight and stop taking the drug?

Frustratingly, when people stop taking semaglutide, the hunger hormones that they were suppressing come back to baseline, often resulting in gaining weight back. One study showed that a year after stopping semaglutide, participants regained two-thirds of the weight they lost and saw cardiometabolic risk factors — like HbA1c and blood pressure — increase, as well as prediabetes and diabetes risk [10].

These results suggest that semaglutide may be needed for life to maintain weight loss efforts, but other data show that most people quit taking semaglutide within two years of starting [11]. This is why it is crucial to implement lifestyle interventions alongside semaglutide to support your long-term weight loss efforts. This includes research-backed supplements, like Motus, that support natural GLP-1 production and can help maintain weight loss after semaglutide discontinuation.

Takeaway: If you stop taking semaglutide, it’s important to build a strong foundation of healthy habits to prevent rebound weight gain. This includes a balanced diet, intentional supplementation, and a consistent exercise routine with a combination of strength and cardio.

5. Vision Changes

Some people who take Ozempic notice changes to their vision, such as blurred vision [12]. This may occur in those who take Ozempic for diabetes management and have rapid blood sugar changes as a result. These rapid swings in blood sugar can exacerbate diabetic retinopathy, or worse.

A new study in JAMA Ophthalmology indicated that Ozempic use is linked to a condition called Nonarteritic Anterior Ischemic Optic Neuropathy, or NAION, which is a condition where blood to the optic nerve is blocked, causing blindness [13]. While this was only an association study, meaning it could not establish causation between semaglutide and NAION, this is a concerning result and requires more research to understand the mechanism.

Takeaway: Semaglutide may cause vision changes due to blood sugar swings, diabetic retinopathy, or eventually NAION. If you notice any vision changes, talk to your health care provider immediately.

6. Pancreatitis

One of the commonly reported side effects of Ozempic is pancreatitis. It’s even listed as a warning label on Ozempic’s packaging as a potential serious side effect of taking the drug. Pancreatitis is a condition where the pancreas becomes inflamed, which can lead to necrosis of the pancreas or, if pancreatitis becomes chronic, a buildup of scar tissue in the pancreas, which affects function [14].

However, research has not reached a consensus as to whether Ozempic causes pancreatitis. In one study of a group taking Ozempic and a placebo group, pancreatitis occurred in 9 patients in the semaglutide group and 12 in the placebo group [15]. Another review of three high-quality RCTs included a total of 9,347 semalgutide-treated and 9,353 placebo-treated patients with type 2 diabetes, and found no link between Ozempic and instances of acute pancreatitis [16].

Pancreatitis is a relatively common condition in adults and can be caused by other factors, like gallstones, alcohol consumption, and a high-fat, poor diet in the long term [17]. This is another reason why it’s important to make lifestyle changes alongside semaglutide use, especially if you have a history of poor health habits.

Takeaway: Pancreatitis has not been confirmed as a side effect of Ozempic, but since it is common in adults and may occur alongside a poor diet, make sure to reduce your alcohol and processed foods intake while taking semaglutide. If you experience severe abdominal pain or pain that radiates from your abdomen to your back (with or without vomiting), stop using Ozempic and call your health care provider right away.

7. Thyroid Cancer

If you’re taking Ozempic, you may have noticed that there is a warning on the box that says Ozempic may increase your risk of thyroid cancer [18]. However, this is based on animal model studies, where semaglutide caused both cancerous and noncancerous thyroid tumors in mice and rats. Until recently, there were no human model studies evaluating this claim [19].

However, in 2024, a cohort study was published that indicated there was no significant association between semaglutide and elevated thyroid cancer risk during an average follow-up period of 3.9 years [20]. Researchers acknowledge that they cannot say there is zero increase in risk, but it is low enough to be statistically insignificant.

Takeaway: More research is needed to establish that there is no increase in risk of thyroid cancer from taking semaglutide. However, existing human studies show increased risk is low. If you have a history of thyroid cancer or dysfunction, talk to your health care provider before taking semaglutides. If you’re taking semaglutide and notice a lump in your neck or experience voice changes, difficulty swallowing or breathing, or pain in your neck/throat, stop taking Ozempic and contact your healthcare provider immediately.

8. Changes in Taste

There have been reports of changes in taste among those taking semaglutide. Some say they have a metallic taste in their mouth, or even find that sweet foods taste bitter. Study results are mixed, with some indicating that taste is heightened, meaning that less of a food (whether it’s sweet, spicy, salty, etc.) is needed to satisfy taste [21]. Another study suggests that taste sensation is dulled by semaglutides and that all foods taste less enticing [22]. Taste tends to return to normal when you stop taking the drug.

Ultimately, the outcomes of both studies seem to be similar, in that heightened or decreased taste sensation results in people eating less, which contributes to their weight loss. Many people even find it easier to reach for healthier foods and reduce consumption of processed foods [23].

Takeaway: If you experience taste changes while taking semaglutide, experiment with different seasonings to make food that is to your liking. Also, focus on whole foods that are high in lean protein to support satiety, nutrient density, and maintenance of muscle mass since you are eating less.

9. Stomach Paralysis

Stomach paralysis, clinically known as gastroparesis, is when stomach emptying slows because the stomach muscle no longer contracts properly, resulting in food not moving through the digestive tract at the proper pace. Symptoms can include nausea, vomiting, abdominal pain, and bloating.

Studies have shown that taking semaglutide can increase the risk of gastroparesis, especially in those with type 2 diabetes [24]. One study found that starting at 6 months, through 24 months, people with type 2 diabetes on semaglutides were at a higher risk of gastroparesis than those who had type 2 diabetes and were not on semaglutide [25].

Takeaway: Fortunately, you can take measures to reduce your risk of gastroparesis, even if you are a type 2 diabetic and on semaglutide [26]. Try to eat smaller, more frequent meals to avoid feeling overly full. Also, stay adequately hydrated and reduce your intake of high-fat and high-sugar foods, since these are harder to digest. If you are diabetic, keeping blood sugar levels in a healthy range will also help reduce your risk of gastroparesis.

Using Motus to Support Sustainable Weight Loss

Of course, semaglutide isn’t the only way to lose weight. We know that lifestyle interventions, like diet, exercise, sleep, supplementation, and stress management, are crucial with or without the use of semaglutide, and perhaps become even more important if you are discontinuing semaglutide use.

For those seeking an alternative to semaglutide medications, Motus offers a promising solution with potentially fewer side effects. This research-backed supplement combines five powerful ingredients — taurine, Berbevis®, Siliphos®, nicotinamide, and ALA — into a single daily capsule that has undergone over eight years of rigorous testing. Clinical trials in mouse models demonstrate impressive results: over 25% reduction in fat mass while preserving lean muscle, 28% cholesterol reduction, an 812% enhancement in GLP-1 efficacy, and a 35% boost in energy levels.

Currently undergoing large-scale human clinical trials, including a direct GLP-1 comparison study, Motus represents a natural approach to weight management that works synergistically with healthy lifestyle choices, including proper nutrition, regular exercise, adequate sleep, and stress management.

However, Motus may come with some side effects. Those who take Motus in excess on an empty stomach may experience GI discomfort, which is why we recommend taking Motus capsules twice during the day with food. There have been reports of minor headaches, which dissipate after taking the product for some time.

Takeaways

Semaglutide medications like Ozempic are widely celebrated for their dramatic weight loss results, but a growing body of evidence reveals concerning lesser-known side effects that extend far beyond the commonly discussed nausea and fatigue.

These hidden complications include significant bone and muscle loss during rapid weight loss, facial changes, potential vision problems, stomach paralysis that can impact digestion, and, discouragingly, the high likelihood of rebound weight gain once users stop taking the medication.

While some side effects, like taste changes and pancreatitis risk, remain under scientific debate, the consistent pattern of muscle and bone loss, combined with the dependency created by these medications, raises important questions about long-term health consequences.

Lifestyle changes, like exercise, diet, sleep, stress management, and supplementation, are crucial to maintaining your health both on and off semaglutide treatment. If you’re looking for an alternative to semaglutide but still want to bolster your weight loss efforts, try Motus, a research-backed supplement that aims to provide similar weight management benefits through natural GLP-1 enhancement. Sustainable weight loss without the severe side effects associated with prescription semaglutide is possible — and it’s up to you.

References:

Emily Johnson, MS, RD, is a health editor and writer with expertise in research, metabolic health, and glucose management. She has written and edited for several health tech companies, including Tonum, Veri, Oura, Doximity, and InsideTracker. When she is not writing for Tonum, she can be found reading novels, writing her newsletter, traveling, or getting some exercise with her rescue dog, Ponyboy.

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