According to the latest NHS data, 64% of adults in England are classified as either overweight or obese. And with the NHS spending over £11bn a year to treat the disease, the demand for effective medical solutions is greater than ever.
It’s no wonder Ozempic, Wegovy and Mounjaro have become hot topics of conversation. Yet there is still much confusion around these drugs, how they work, who can take them and what risks they might carry. For example, did you know that Ozempic is not actually licensed for weight loss? It’s only available as a medication for treating Type-2 diabetes.
Now, a new survey, the Numan State of Obesity Report, reveals that a quarter of us (26 per cent) rely on social media to tell us about medications like Mounjaro and Wegovy – twice as many as gathering facts from the NHS (13%) or their local surgery (7%).
Here, we ask the experts what you need to know about the different types of medication, their safety, side effects, and who they’re actually for.
What exactly are Wegovy, Ozempic and Mounjaro?
The two most well known examples of what many people mistakenly call ‘weight loss jabs’ are semaglutide which is prescribed as Wegovy and Ozempic, and tirzepatide, which is prescribed as Mounjaro. “There are several key differences between these,” adds Professor Frank Joseph, professor of Endocrinology, Diabetes and Metabolism, and the clinical lead for weight loss at Goodbody Clinic. “Firstly, it’s important to note that Ozempic is not actually a ‘weight loss jab’ – it is only approved in the UK for type-2 diabetes management among adults over the age of 18 years.
“By comparison, Mounjaro is approved for weight management in people living with and without Type-2 diabetes. AndWegovy is also approved for weight loss and weight management in people living with and without Type-2 diabetes.
GP Dr Bryony Henderson, obesity management expert and medical director at Numan continues, “Mounjaro and Wegovy are prescription drugs designed to help people lose weight by reducing appetite, increasing feelings of fullness, or slowing down how quickly your body absorbs food.
“The medications that are currently capturing the most attention are ‘GLP-1 receptor agonists’. This is a complex way of saying that the drugs work by mimicking the natural hormone, GLP-1, in order to regulate your blood sugar levels and control appetite.”
Dr Henderson warns, “It’s important to note that, unlike fad diets or over-the-counter slimming products, these are regulated medical treatments that should only be used under the supervision of a healthcare professional.”
Who can be prescribed Ozempic, Wegovy and Mounjaro?
Obesity management medications are not for everyone. “These drugs are typically prescribed for people who have obesity, defined as a body mass index (BMI) of 30 or above, or those with a BMI of 27 or higher who also have weight-related health issues such as Type-2 diabetes, heart problems or high blood pressure,” says Dr Henderson.
“These are ‘comorbidities’ make it more likely for a person who is overweight or obese to have serious health complications in the future, hence the use of medication to help them bring down their weight and reduce their chance of becoming more sick.
“Crucially, these medications are not a ‘quick fix’ or a ‘magic jab’. They aren’t intended for anyone looking to shed a few pounds for cosmetic reasons or a short-term goal like fitting into a dress for a wedding or going on holiday. They are designed for those who are clinically obese, where weight is contributing to serious health risks, and where other methods – like diet and exercise alone – haven’t been enough.”
How much can I lose while taking Ozempic, Wegovy or Mounjaro?
Prof Joseph says, “While Ozempic is not licensed for weight loss, those taking it to treat their type-2 diabetes symptoms have found that it does impact their weight. One study found that semaglutide (the active ingredient in Ozempic) is effective for weight loss at three and six months for those with obesity. In the study, 57.3% of patients achieved a minimum of 5% weight loss in three months. 87.3% achieved 5% weight loss within six months.
“The SURMOUNT-1 clinical trial (with non-diabetic patients with obesity) showed that Mounjaro is highly effective for weight loss. Over 72 weeks, patients lost up to 22.5% of their body weight.
“As for Wegovy, clinical trials prove that – alongside a healthy diet and physical activity – Wegovy can be highly effective, with patients losing an average of 15% of their body weight over the span of 68 weeks. In another trial, the SELECT trial, patients lost an average of 10.2% of their body weight when taking Wegovy, over the span of four years.”
Which is most effective out of Ozempic, Wegovy or Mounjaro?
“Mounjaro tends to get better results from weight loss than Ozempic and Wegovy,” says Professor Joseph. “The JAMA Internal Medicine Study compared Ozempic and Mounjaro and found that Mounjaro led to more significant weight loss compared to those who took Ozempic. The longer that patients took each drug, the more significant the gap became.”
Are Ozempic, Mounjaro and Wegovy safe to take?
There have been fresh safety concerns following the death of nurse Susan McGowan, 58, from North Lanarkshire, whose death certificate recorded “the use of prescribed tirzepatide” – which is sold as Mounjaro – as a contributing element.
“These treatments are prescription-only for a reason – they require close medical supervision to ensure they are used safely,” says Dr Henderson. “You should always consult a doctor or clinician before you start taking them.
“They should also be used as part of a holistic programme to help a person become healthier,” she adds. “When you are prescribed obesity management medication, your healthcare provider will usually give you a treatment plan that also involves making changes to your diet and exercise routine. In other words, these medications are always intended to be part of a broader approach to weight management, not a quick fix – for example, at Numan, we provide all our obesity patients with 1-to-1 behavioural coaching support to help them achieve holistic, sustainable results.
“It’s essential to follow your healthcare provider’s instructions carefully, as using these medications improperly does come with risks and may reduce their effectiveness.”
“Another key thing is that you should never attempt to purchase obesity medications through social media or unregulated online platforms. As tempting as it may be to cut costs, obtaining these drugs without a prescription is illegal and highly dangerous. There have been reports of fake or contaminated weight loss drugs being sold online, which can lead to serious health risks. Always ensure your medication is coming from a regulated, reputable provider approved by the Care Quality Commission (CQC).”
What are the side effects of Ozempic, Mounjaro and Wegovy?
Like all medications, obesity management medications can cause side effects. “These injections are considered safe if taken correctly,” says Prof Joseph. “It is crucial to share your medical history and current medical conditions with your clinician before starting on these drugs. This allows them to determine whether a specific injection is suitable for you and if there will be any potential interactions.
“The full list of side effects can always be found on the Electronic Medicines Compendium.”
Dr Henderson adds, “The side effects are linked to the natural hormones that the medication mimics – which means the side effects are largely predictable. Mild side effects such as nausea, constipation, stomach cramps, and diarrhoea are relatively common and tend to ease as your body adjusts to the medication.
“More serious side effects are rare but can include pancreatitis (inflammation of the pancreas), gallbladder problems, or allergic reactions. This is part of why it’s so important to work with a reputable provider who can help you understand and monitor any side effects you may experience, as well as how to manage them.”
Prof Joseph adds, “In general the benefits outweigh the risk of treatment if it is used in the right patients. The thing that is important is having good clinical supervision to ensure that the significant weight loss and reduction in overall intake of food does not impact on nutritional deficiencies, bone density and muscle loss.
“These medications and their effects are closely monitored and clinicians will report any untoward effects via the Yellow Card Scheme.”
Will I put weight back on if I stop taking Ozempic, Wegovy or Mounjaro?
“Weight regain can occur when you stop taking medications such as Wegovy or Mounjaro,” says Professor Joseph. “This is however dependent on a number of factors and is very individual. Your clinical team will be able to advise on ways to reduce the risk of this happening by providing you with the support you need to make healthy, sustainable lifestyle changes to keep the weight off for good.”
However, it is thought to be perfectly safe to use these medications for prolonged periods. “These medications are designed for long-term use as it is increasingly recognised that obesity is a chronic relapsing and remitting illness,” says Prof Joseph. “In some individuals, long-term use may be necessary but only time gives the answer. With the right support you can make healthy and lasting lifestyle changes to try and help you maintain your new weight after ceasing your medication.
Are there any extra benefits of taking Ozempic, Mounjaro and Wegovy?
The impact of these medications appear to be far reaching. “One thing that people should know about these medications is the benefits they can have on heart health,” says Professor Joseph.
“Semaglutide, for example, was developed as a form of type-2 diabetes treatment, but it has proven effective in aiding weight loss and reducing the risk of obesity-related health issues.
“I was a co-investigator in the study, which found that semaglutide can not only help patients with or without type-2 diabetes lose weight and get healthier but also reduce the risk of heart attack, strokes and cardiovascular death among those who have previously had a heart attack or stroke.
“The study involved patients who have had a previous heart attack or stroke and explored how semaglutide could reduce the risk of having another event. While some did lose weight, the key takeaway from the study is that patients weren’t having as many heart attacks or strokes.”
