Judie Thompson recently drove to a pharmacy 45 kilometres from home to replenish her dwindling supply of the drug she says changed her life. Thompson, 64, from Brisbane, began using the drug in March to manage her type 2 diabetes. Since then, she has lowered her insulin usage from five injections a day to just two – and lost 20 kilograms.

“It’s changed my life totally,” she says. “I was 107 kilos when I went on it, and I started losing weight as well as noticing how well my insulin was working.

“I walk my dogs, which I haven’t done in 10 years. I’m so happy to be me now.”

The drug, Ozempic, which comes as a weekly injection, has been approved in Australia for treating type 2 diabetes but is also sought after because it can help with weight loss, as is its weight-loss-specific counterpart, Wegovy, in the United States. Ozempic is now a “Hollywood drug”, according to some reports. Asked how he got to look “so ripped”, billionaire Elon Musk tweeted it was down to “fasting … and Wegovy”.

Now there’s a global shortage of Ozempic. It will not be available in Australia until April, affecting people who use the drug to manage their diabetes.

What’s causing the shortage? Who should be using Ozempic? And is it a magic shortcut for weight loss?

What’s Ozempic (and what’s Wegovy)?

Ozempic was created by Danish drug company Novo Nordisk in 2012 and approved for use for type 2 diabetes in the US in 2017 and in Australia in 2019. In July 2020, it was listed on the Pharmaceuticals Benefits Scheme (PBS) so that it costs about $40 (or $6.60 with a concession card) for a monthly course of weekly injections. The same amount on a private script, or “off label”, can cost $130 or more.

About 1.3 million Australians were newly diagnosed with type 2 diabetes between 2000 and 2020, according to the Australian Institute of Health and Welfare. Diabetes is caused by the body’s inability to use and/or produce insulin, a hormone that controls blood glucose levels.

In clinical trials by Novo Nordisk, it was discovered that semaglutide, which Ozempic contains, had a dual effect: it could also lead to weight loss in patients.

Semaglutide stimulates cells that make insulin while suppressing glucagon, affecting blood glucose levels, says leading endocrinologist and obesity specialist Professor Joseph Proietto at the University of Melbourne. “Semaglutide is an analog of one of our own hormones that we make in our small bowel called glucagon-like-peptide-1 [GLP-1],” adds Proietto, who established the weight control clinic at Austin Health. He says GLP-1 slows gastric emptying “so that it makes you feel fuller for longer, and then it goes to the brain and suppresses hunger. And both of those actions help with weight loss.”

“It is known people who have diabetes have more trouble losing weight.”

In clinical trials of Ozempic by Novo Nordisk, people with type 2 diabetes improved their blood sugar control and lost an average of between 2.75 and 3.56 kilograms more than people using a placebo by week 30. In clinical trials of Wegovy by Novo Nordisk, participants considered obese but who did not have diabetes lost an average of 15.3 kilograms over 68 weeks compared to those who lost three kilos with diet and exercise alone.

“It is known people who have diabetes have more trouble losing weight,” says Proietto. “Also, Wegovy is higher dosage and [that] study was of people who didn’t have diabetes.”

Proietto advised Novo Nordisk on Ozempic and iNova Pharmaceuticals on the weight-loss drug Contrave, which is common practice for experts.

Wegovy was approved in the US in June 2021 for chronic weight management in adults with obesity or who are overweight with at least one weight-related condition, such as high blood pressure, type 2 diabetes, or high cholesterol. In September, the drug was approved for use in Australia for chronic weight management, as an adjunct to diet and exercise, but it’s not on the PBS and is not available here yet. Novo Nordisk has said in a statement it is working hard to make it available for patients living with obesity.

The Therapeutic Goods Administration, which regulates medicine supplies in Australia, points out that while they’re both semaglutide drugs, Ozempic and Wegovy are not interchangeable: they have different approved indications and uses, and involve different dosages and injecting devices.

Why is there a shortage of Ozempic?

“The worldwide shortage of semaglutide started to affect Australia in early 2022,” says the TGA, “when Novo Nordisk couldn’t supply enough Ozempic to meet an unexpected increase in demand due to off-label prescribing for weight loss.” The TGA adds that off-label prescribing, where doctors prescribe the drug in a way it wasn’t specifically approved for, is not unusual, “particularly for uncommon diseases and conditions or under-represented patient groups”.

“Making Ozempic involves a complex process to produce semaglutide using specialised equipment in a unique manufacturing setting,” the TGA said. “This means that re-establishing supply for a global shortage will take some time.”

Data from the federal Department of Health has shown the number of scripts issued monthly for the drug nationally increased six-fold over 2021 to more than 86,000 in December.

It’s been rumoured that people are taking Ozempic to “fit into their bridesmaid’s dresses,” says endocrinologist Samantha Hocking, president of the National Association of Clinical Obesity Services, who has advised Novo Nordisk and Eli Lilly. “[But] I don’t think there’s any people who are normal weight getting these medications. You can’t just purchase Ozempic, it has to be prescribed by a doctor.

“There are 8.5 million people [living with obesity] and eligible to be prescribed this medication by their doctor. And that is a huge demand for medication.”

Meanwhile, Ozempic and other semaglutides have been going “viral” on social media. The TikTok Ozempic hashtag has been viewed more than 295 million times and there are Ozempic hashtags for various countries, including “Ozempicaustralia”, which is the most popular, with 18.2 million views. “If you spend enough time at the right dinner parties or on TikTok, you’ll eventually hear about Ozempic,” said a report in Town and Country in the US in August.

Prescription-only medicines such as Ozempic can’t be advertised to the public in Australia, the TGA says, and it is investigating alleged unlawful advertising of Ozempic and meeting with social media platforms to underline Australian laws on this issue.

“We don’t want new patients initiated on drugs that are in short supply, like Ozempic.”

Given the shortage of Ozempic, health professionals have been advised to prioritise people with type 2 diabetes. “The guidance for our GPs is very straightforward,” says Dr Karen Price, president of the Royal Australian College of GPs. “We don’t want new patients initiated on drugs that are in short supply, like Ozempic.”

Pharmacists can reject off-label scripts from patients who have been prescribed the drug for weight loss. “It’s really frustrating for patients that they can’t get access to a really important medication to help manage diabetes, which is a serious chronic health condition,” says Anthony Tassone, a pharmacist and president of the Pharmacy Guild of Australia’s Victorian branch. “Most patients that have been seeking Ozempic, from my experience, have been diabetes patients, but there has been a noticeable increase generally and it’s very difficult to quantify what proportion would be patients who are using it for the purposes of weight loss and not primarily for diabetes control.”

The shortage of Ozempic has also prompted doctors to prescribe alternatives for patients with type 2 diabetes, including Trulicity (dulaglutide), made by drug company Eli Lilly, which has led to a shortage of that drug too. Patients who have been prescribed Ozempic or Trulicity have been advised by the TGA to have their treatment “immediately reassessed” by their doctor.

Why are drugs used to treat obesity?

Two in three Australian adults are obese or overweight. Nearly a third of Australians live with obesity, categorised by a body mass index (your weight divided by your height squared) over 30. The normal BMI for men and women is 18.5 to 24.9. Anyone with a BMI between 25 and 29.9 is considered overweight.

“A patient who has been living with obesity for some time has almost certainly tried diet and exercise,” says Professor Michael Cowley, the inventor of weight-loss drug Contrave, who heads the Department of Physiology at Monash University and has advised Novo Nordisk. “So while it’s appropriate to say ‘Have you tried diet and exercise?’, it’s also almost certainly true that they have. So I don’t think that should be a barrier to using a medicine.”

Proietto says using drugs to help manage obesity is no different to using them for other health conditions. “We take a lot of drugs [for other conditions],” he says. Ozempic has “two big pluses going for it”: “It’s convenient because it’s normally only one injection a week, which only takes you a minute to do; and two, because of the reasonable cost.”

Without such drugs for obesity, he says, “you can keep weight off – you have to fight hunger, but it is possible – but then you’re going to be at the mercy of the hormones”.

In a study by Proietto of people with obesity who lost weight, it was found that appetite-regulating hormones such as leptin were reduced after weight loss, leaving you hungrier than when you started. “Some form of hunger-suppressing medication is required to maintain weight loss for life,” says Proietto, “because of significant hormone changes after weight loss occurs.”

“Some of us have genes that make us more likely to gain weight, and we live in a world that aggressively markets delicious food that’s high in calories.”

Nick Fuller, who runs clinical research at Charles Perkins Centre Royal Prince Alfred Hospital Clinic and the University of Sydney, says the development of drugs that mimic the function of GLP-1 in the body has the potential to change the management of obesity. “For a long time the weight-loss drugs available were either amphetamine-like stimulants or ones that blocked the absorption of fat, which were unpopular.

“It’s an effective management tool for obesity, but first-line therapy for those needing to lose weight should be evidence-based lifestyle intervention, not drugs,” says Fuller, who has run clinical trials for a range of weight-loss drugs including Ozempic.

Cowley says obesity is a complex problem. “I think we need to be very careful about stigmatising obesity,” he says. “A growing number of scientists and physicians believe that obesity is a disease of our environment. Some of us have genes that make us more likely to gain weight, and we live in a world that aggressively markets delicious food that’s high in calories.”

Does Ozempic have side effects?

People who have used Ozempic commonly experience nausea and diarrhoea, says Novo Nordisk. Vomiting, stomach pain and constipation are other potential side effects. The Ozempic website also warns of gall bladder stones, changes in vision and low blood sugar. It says the most serious potential side effects are pancreatitis - inflammation of the pancreas which causes severe stomach pain that doesn’t go away - and allergic reactions that include rashes, shortness of breath and swelling of the lips and tongue.

Gemma Rose, 24, from Brisbane, was categorised as obese and used the drug as part of a weight-loss program supervised by a GP and nutritionist. “The first few days I was not hungry at all,” she says. “[I remember thinking] If I eat anything right now, like, I’m actually going to throw up.”

She suffered from vertigo initially but it subsided and she was able to continue to use the drug and go on to lose eight kilograms.

“It was worth it,” she says.

Judie Thompson says Ozempic suppressed her appetite so dramatically she had to remind herself to eat. “I had no appetite whatsoever,” she says. “I had to put a timer on my phone to remind me to eat, so I could stay within my sugar boundaries.”

“There’s a wide range of sensitivity to the effects and side effects of Ozempic, and it can be genetic.”

Some reports overseas detail “incessant vomiting”. Proietto, who has treated patients with Ozempic, says there is a small cohort who present with nausea so severe they can’t function. “You can’t predict who is going to react and get certain side effects,” he says. “There’s a wide range of sensitivity to the effects and side effects of Ozempic, and it can be genetic.”

He says the drug may not work for some users. “A small dose [of Ozempic] suppresses their hunger very nicely, whereas you have others at the other extreme that it doesn’t work [for] at all.”

Ozempic is not recommended for some people: those who have had thyroid cancer or have a family history of medullary thyroid cancer, or an endocrine system condition called multiple endocrine neoplasia syndrome type 2. Pregnant women are not advised to use it and women should stop using it at least two months before attempting to become pregnant.

Are these drugs a magic bullet for weight loss?

If some of the rave reviews on social media are anything to go by, the answer would be yes, however Proietto says otherwise. “There’s no magic bullet for weight loss,” he says. “This is a useful drug because it helps people, but they need to be very careful with diet – you need to eat less than you burn to lose fat.”

Cowley says: “I don’t think a person with a normal BMI needs a medicine this strong. I don’t think there’s any evidence of health benefits in losing weight below a BMI of 25.”

Fuller says: “Follow-up trials have shown that people who use semaglutide for weight loss regain two-thirds of the prior weight loss within a year of ceasing it. When you come off the drug – just like any other medication – it stops working. Consequently, people’s hunger comes back and they put the weight back on they lost.”

For Thompson, being on Ozempic was a circuit-breaker and she found herself reaching for healthier food. “I’d eat corn thins with tomato and [a] little ham, and keep it pretty low-carb,” she says. “For dinner I tried to have a proper meal and eat healthy.” This change in her diet has become a habit, she says.

“There’s no magic bullet for weight loss. This is a useful drug because it helps people, but they need to be very careful with diet.”

Despite having type 2 diabetes and struggling to get Ozempic easily, she sympathises with people who want it to manage their weight. “The drug is a drug for more than one illness,” she says.

Still, she has had to go through a patch of four weeks without it and her insulin use doubled to four injections a day. Since then, she has found supplies at a lower dose, but they will last only a fortnight. ”Hopefully, I can soon drop them [insulin use] back again if I can continue to get it [Ozempic],” she says. “My biggest fear is the insulin use will go up again, which means I will gain weight again even if I stay within my new eating habits,” she says, adding that she feels self-conscious injecting herself in public. ”I check the room: who’s looking at me, you know, are they going to think I’m some kind of drug addict injecting myself?“

Gemma Rose was able to find Ozempic again after several weeks of looking. “I have five weeks left of doses and then I’m back on nothing.” She hopes she can stick to her healthy lifestyle changes. “I still feel like I’ve got these good habits even without it that are really great.”

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