Hollywood stars are dropping dress sizes, TikTokers are buzzing, Elon Musk says it keeps him looking “fit, ripped and healthy”: semaglutide seems to be the most-hyped drug of the moment.
The demand for semaglutide, marketed under the brand names Ozempic and Wegovy, is so high that maker Novo Nordisk has been struggling to produce enough. It belongs to a class of drugs known as GLP-1 receptor agonists that have been hailed as a gamechanger for diabetes and obesity.
“We’ve been seeking an appropriate weight-loss medication for a very long time,” says Wellington endocrinologist Rosemary Hall. “Pretty much all the weight-loss medications that have come before have had quite significant side effects, whereas these groups of medications are really well tolerated and they all, to a greater or lesser degree, cause weight loss and improvements in blood glucose levels.”
GLP-1 is a powerful gut-brain hormone involved in satiety. It signals to let us know we are full and should stop eating and also slows down the rate the stomach empties, so we feel fuller for longer. Most importantly for diabetics, it stimulates the pancreas to produce more insulin when blood sugar levels are high.
Although Ozempic is now approved to treat diabetes in this country, the drug isn’t funded yet. Nor is another drug from the GLP-1 receptor agonist family, liraglutide (Saxenda), which is approved here to treat obesity. Both are delivered via an EpiPen injection that can be self-administered, although it seems oral versions of these types of drugs are on their way.
GLP-1 receptor agonists are said to quieten “the food noise” in people’s heads, with reports that cravings disappear. There is also the possibility they could be used to treat other addictions, with some patients saying that since they started taking semaglutide, they have lost compulsive behaviours ranging from drinking alcohol and smoking cigarettes to biting fingernails and addictive shopping.
There are some potential side effects – nausea, diarrhoea and stomach bloating are the more common – and these drugs are not without controversy. There has been some push-back from the body-positivity movement, for instance. And in the US, the term “Ozempic face” has been coined to describe the facial sagging and hollowed-out appearance caused by losing a lot of weight very rapidly. Also, research is beginning to suggest that those who stop taking the medication will gradually regain at least some of the weight.
Such is the demand for these drugs to help with weight loss that there have been shortages for those who need them to treat type 2 diabetes. Pharmac now funds two brands, Victoza (another version of liraglutide) and Trulicity (dulaglutide), for diabetes patients who are at high risk of complications.
“These drugs are part of the gold standard of care for diabetes,” says Hall. “They improve kidney function and reduce the potential cardiovascular complications of the disease. We had been asking for them for a long time.”
The diabetes patients for whom Hall is prescribing GLP-1 receptor agonists are finding them easy to manage and effective. “They cause a significant reduction in glucose levels and most people lose quite large amounts of weight.”
New-generation drugs are already emerging, such as tirzepatide (Mounjaro), which mimics the effect of two hormones rather than just one and there’s some evidence it may lead to greater weight loss.
At the moment, self-funding a GLP-1 receptor agonist medicine for weight loss remains expensive. Saxenda is available from clinics here for about $500 a month. But with the healthcare burden that obesity brings, it seems likely that, in time, these therapies will become more accessible.
Hall says they can be considered for those with a body mass index greater than 30 (or above 27 if a patient has other conditions). “At that point, you are at higher risk of developing metabolic complications. And we know that if you lose 5-10% of your body weight, you’re going to have a significant improvement in a whole lot of metabolic factors – things like blood pressure, cholesterol, risk of heart disease, diabetes, osteoarthritis and sleep apnoea.”
