Why diabetes drug Ozempic isn’t a weight-loss injection for all

Ozempic has achieved what many influencers dream of. In just a short time, TikTok videos hailing the injections as a weight-loss miracle racked up more than a billion views. This was partly down to prominent Ozempic users such as Tesla founder Elon Musk, who raved about his effortless weight loss.

But here’s the rub. Ozempic isn’t a lifestyle product, it’s a drug for people with type 2 diabetes. So how did it turn into a hyped-up dieting wonder drug that’s drawing in ever increasing numbers of non-obese people looking to lose a quick few kilos? Dr. Florian Kiefer, Head of the Endocrinology Outpatient Clinic at Vienna General Hospital and specialist in internal medicine with a focus on endocrinology and metabolism, has some answers.

Dr. Kiefer, Ozempic, with the active ingredient semaglutide, was originally developed as a type 2 diabetes drug. How does it work?

Dr. Kiefer: The active ingredient semaglutide contained in Ozempic is referred to as a GLP-1 receptor agonist. GLP-1 is a human gut hormone secreted after food intake – particularly after consuming carbohydrates. It regulates insulin secretion and with that, blood glucose levels. The active ingredient semaglutide binds to the same receptor as the natural hormone GLP-1, but activates it even more strongly and for longer. This lowers blood sugar levels, which is why it’s an effective diabetes medication. What semaglutide also does, however, is evoke a feeling of fullness in the brain, causing you to consume fewer calories. And at the beginning of the treatment especially, it delays gastric emptying, making you feel full for longer. Many users therefore also experience a significant reduction in weight. This, in turn, positively impacts their diabetes, as weight loss also improves the body’s sugar metabolism and insulin sensitivity. As a result, other blood sugar-lowering medications become more effective again.

These days, when Ozempic is mentioned, we don’t hear much about diabetes. Instead, it’s being touted solely as a weight-loss wonder drug. How has this come about?

The weight-loss side effect is also well documented in obese people who don’t have diabetes, including in studies like this one from the University of Leicester, clinical practice and observational studies. On average, people who take semaglutide in conjunction with lifestyle interventions lose about 15 per cent of their body weight in the space of a year. These results come close to those achieved by a gastric band. That’s why the active ingredient is also approved for the treatment of obesity. However, Ozempic is intended for patients with type 2 diabetes. Strictly speaking, that means giving Ozempic to obese people who don’t have type 2 diabetes would considered off-label use. Wegovy, a higher-dose drug with the same active ingredient, which is specifically tailored to treat overweight and obesity, is already available in the USA and some other countries. However, it’s not (yet) on the market here in Austria (editor’s note: it’s not yet available in Switzerland or Europe due to supply chain issues). The drug Saxenda, with the active ingredient liraglutide, can be used as an alternative. It’s already on the market in Austria and achieves similar effects.

So, are the medications you’ve mentioned for severe obesity a non-invasive alternative to stomach reductions?

Of course, surgery can achieve more significant weight reduction than medication. However, use of the drug can be particularly useful in preparation for these kind of surgeries – losing weight reduces the risk of the surgery. Sometimes, health insurance providers even pay for it. If not, patients in Austria (editor’s note: and Switzerland), have to pay for the prescription drug if they don’t have type 2 diabetes. A four-week supply of Ozempic costs about 145 euros in Austria (about 135 Swiss francs). The question of whether this is «worth it» has to be determined in advance as part of a diagnostic conversation with an expert in metabolism. After all, not every patient responds well to the treatment. The people who achieve particularly good results are the ones who have difficulty controlling their food intake, as the drugs primarily create a feeling of fullness. However, they don’t increase basal metabolic rate, which is why patients need to ensure they’re getting enough exercise during treatment.

At what point are weight loss drugs indicated? What BMI?

Weight loss drug therapy may be considered if someone’s body mass index is greater than 30 kg/m2. It might also be indicated for those with a BMI greater than 27 kg/m2 who have obesity-linked comorbidities such as hypertension, prediabetes or elevated blood lipids.

Effortless weight loss sounds almost too good to be true …

Drug therapy is by no means a replacement for a healthy lifestyle. What’s absolutely essential for weight management is the creation of a multimodal therapy concept. As well as medication, there should also be nutritional coaching and an exercise regime – at least 150 minutes of gentle strength- and endurance training per week. If necessary, psychological support is also important, as obesity is often accompanied by depression.

What are the potential side effects of medication?

About a quarter of patients report nausea, especially at the beginning of therapy, but this usually improves with continued use. Vomiting, diarrhoea and constipation might also occur. Some less common side effects include reactions at the injection site, dizziness and an elevated heart rate. Extreme caution is required around pre-existing conditions such as gallstones and colic, severe reflux or pancreatitis, which may also be contraindications. Some patients also report a severe loss of appetite, but this is usually only the case if the dosage is too high or has been increased too rapidly. That’s why it’s important that anyone taking the drug is fully informed in advance, and educated in both its use and correct dosage increases. This also includes paying attention to your eating habits and, if necessary, adjusting the dosage after consulting a doctor.

What’s the typical treatment process?

There are no strict guidelines, but treatment is of course determined on an individual basis. That being said, a therapy goal should be agreed upon in advance. The minimum goal is a five per cent reduction from baseline weight about 12 weeks after starting therapy. During this period, the patient injects the drug themselves via pen. Liraglutide is administered once daily, whereas semaglutide is injected once weekly.

It’s important that the patient adjusts their eating habits and exercises regularly during treatment. If the therapy is successful, it’s up to those involved how long it’ll continue. The goal is for patients to use the therapy to change their behaviour in such a way that they may be able to maintain their weight without needing medication in the future.

The hype surrounding Ozempic has led to the medication also being used by people who’re of normal weight – or only slightly overweight – as a quick fix to shed a few kilos. What do you make of this?

The German endocrinologist Professor Harald Schneider, for example, has warned that it’s unknown whether the drug might cause more severe side effects in people of normal weight than in obese people. For the latter, of course, the dosage is adjusted to their higher weight. And the Guardian has even reported on an «eating disorder in an injection» ...

In Austria (editor’s note: and Switzerland), advertising prescription drugs to consumers is banned. But this obviously doesn’t stop people in this country finding out about a so-called weight loss injection through various media outlets. I’m very critical of fads like these – there have been a few them in the past, for example, around using growth hormones for weight loss. And I’m especially critical in light of the fact that they’re taking on an unprecedented dimension because of social media. Of course, when people affected learn about new therapy options, it’s a positive thing. But misuse is occurring more frequently. For instance, when people use these treatments even when they’re not medically indicated. These drugs aren’t designed to allow someone with a normal weight and a healthy metabolism to achieve a beauty ideal. Not only that, but we can’t rule out the possibility of people with eating disorders – particularly in countries like the US – being able to obtain these medications due to easier access to drugs.

Plus, my colleagues and I are now suddenly seeing people who aren’t overweight or obese, who don’t meet the criteria for a prescription, come into the surgery and demand a prescription. Physicians have a great deal of educational work to do around this. After all, the high demand for the drug is already causing supply bottlenecks, which is jeopardising the care of patients with type 2 diabetes.

Tirzepatide is another active ingredient on the starting blocks that achieves even more significant weight loss. Can patients go for that instead?

The EU Commission has approved the first GIP/GLP-1 receptor agonist tirzepatide (brand name Mounjaro) for the treatment of adults with type 2 diabetes.It’s part of a new class of substances. Due to its dual mode of action, tirzepatide has an even greater impact on blood glucose levels and body weight. In clinical studies, it’s also been successfully used for obesity. However, tirzepatide is currently only available in the US and the United Arab Emirates. Even though a lot has happened in the field of obesity therapy in recent years, there’s still a lot of room for improvement. For example, there’s a lack of approved effective drugs that not only target appetite regulation but also increase basal metabolic rate or resting energy expenditure. We need to do more research on that.