A new weight loss drug has been approved for use in chronic weight management,  but is it the same as Ozempic and Wegovy? University of Newcastle and HMRI  Immune Health researcher and Accredited Practicing Dietitian Dr Georgina Williams, explains.  

“Both Ozempic and Wegovy (semaglutide) and Mounjaro are injectable medications used for weight loss and management of blood sugar levels. Ozempic and Wegovy act on the receptors of a hormone called GLP-1. GLP-1 helps to regulate appetite and reduce blood sugar levels and so taking these medications enhances these effects in the body.  

“Mounjaro is considered more effective than Ozempic and Wegovy because it acts on GLP-1 receptors as well as the receptors of another hormone called GIP. This hormone has similar actions to GLP-1 and so the dual action has greater capacity to reduce appetite which leads to reduced energy intake and subsequent weight loss and regulated blood sugar levels,” she says.  

So who can be prescribed mounjaro? And how much does it cost? 

Dr Williams says, “Mounjaro can be prescribed by a doctor to anyone with a BMI above 27kg/m2 and weight-related conditions or a BMI over 30kg/m2 alone. It’s not available on the Pharmaceutical Benefit Scheme (PBS) yet so cost is likely to be the largest limitation to its availability at present. Mounjaro costs between $345 -$645 per month, depending on required dose, while Ozempic and Wegovy are only between $8 – $35 per month on the PBS.” 

What are the side effects of Mounjaro? 

Dr Williams says that the side-effects of Mounjaro are similar to Ozempic and include nausea, vomiting, diarrhoea, and constipation.  

“These usually subside after a few months on the drug but the risk of malnutrition is a concern in cases of extreme appetite suppression,” she says.  

The important thing to note is that the effects of the drugs in terms of reduced appetite and better blood sugar management stop once the drug is ceased.  

The importance of a healthy lifestyle 

While Mounjaro can be effective at reducing body weight, once you stop taking the drug and appetite is no longer suppressed. This can lead to increased hunger and potential weight gain. 

“If the drug can’t be continued long-term due to cost or side-effects, weight regain is likely. That’s why it’s important to ensure that people are educated about the role of diet and physical activity for long-term weight and chronic disease management,” says Dr Williams.