They’re often billed – irresponsibly, say doctors – as weight-loss “wonder-drugs” or “miracle” jabs. But amid hype about celebrity crazes and concerns about a counterfeit-riddled black market, healthcare professionals are keen that an important message is not lost: the class of medicines known as GLP-1 agonists, abbreviated to GLP-1s, can transform the health and life of people with obesity.
Although barriers remain, from stigma to affordability, it’s been a milestone year in Ireland for GLP-1s, with Mounjaro becoming available on prescription in the Republic in February and Wegovy following at the end of March.
Wegovy, made by Novo Nordisk, contains semaglutide, the same active ingredient found in the Danish company’s most famous drug, Ozempic, which has been used here for the treatment of type 2 diabetes since 2018. Ozempic remains the most common shorthand for GLP-1s.
The drugs work by mimicking a natural hormone (GLP-1) that’s released after eating, signalling satiety – feeling full – to the brain. This suppresses patients’ appetites and better regulates their blood sugar.
RM Block
Mounjaro is made by US pharma giant Eli Lilly (also known as just Lilly) and, like Wegovy, it is a weekly, self-injectable medicine. Its active ingredient, tirzepatide, is a “dual agonist”, meaning it stimulates the receptors for two hormones in the body: GLP-1 and also GIP, which regulates appetite.
Further clinical breakthroughs are expected to lead to the arrival of new drugs in the coming years – including “triple agonists” and ingredients that preserve lean muscle mass – and, with them, more enlightened thinking about obesity.
Specialists say conversations about these treatments should focus on health gains, not kilogram losses, and that the very real benefits of their long-term use should be disentangled from social-media narratives about the perceived desirability of thinness.
“Four or five years ago, talking about the use of GLP-1s for treating obesity was a little bit taboo,” says Dr Harriet Treacy, a medical doctor who cofounded Beyondbmi, a digital obesity clinic and UCD spin-out company.
“That has obviously changed a lot. There almost isn’t a week that goes by that obesity isn’t discussed in the media in some way, shape or form, and I think, in honesty, that’s a net positive thing.”
New data is one of the main catalysts for this, she says. “There’s increasingly more evidence to show how powerful these medications are in the treatment of the disease of obesity.”
Treacy cites a 2023-published study showing that semaglutide can reduce the risk of heart attacks and strokes by 20 per cent in patients with an existing history of cardiovascular disease. Tirzepatide, meanwhile, has been found to reduce the risk of overweight or obese adults with pre-diabetes going on to develop type 2 diabetes by 94 per cent.
One key unknown – now being explored in a medical study – centres on the drugs’ capacity to help people keep weight off, even if they reduce their dose.
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“It’s very hard to find somebody who has not lost weight on a diet, but you will rarely find people who have maintained that weight loss,” she says.
“That, to me, is the big question that has evaded the diet industry and the medical industry. Okay, great, we can lose weight, but can we keep it off? In a similar vein, we can treat the disease, but can we continue to treat the disease?”
One thing is clear to obesity specialists: healthcare professionals who tell obese patients to “just eat less and move more” are not giving them access to evidence-based care. Treacy says patients often “internalise that bias” and view themselves as failures if they hold on to their weight or stop losing it after a certain point.
“Stigma is a huge barrier,” says Dr Mick Crotty, a GP who specialises in obesity. He runs the Dublin-based private clinic My Best Weight and serves as the clinical lead for obesity with the Irish College of General Practitioners.
“There can be huge disappointment and almost a sense of shame and failure if people don’t respond to these treatments. For me, it’s about helping people understand that no person fails a treatment. The treatment fails the person if it’s not the right treatment for them.”
GLP-1s are “not a reset or kick-start”, nor is it “like taking an antibiotic”, he says. They are, instead, part of a lifelong treatment for chronic disease.
What can happen after patients start taking them is that they will have “almost like a honeymoon period” where they find “food noise” has reduced, their appetite has been regulated and they realise, perhaps for the first time, that their weight is not their fault.
“We’ve treated their subconscious brain, which is very impactful to show people that this is a biological disease,” he says. “And then eventually, at a given dose of a treatment, you will see things stabilising, and their weight will plateau.”
At this point, though patients notice the health and quality-of-life benefits of their reduced weight, their appetite might return a little bit. “And that can scare people,” says Crotty.
This is one reason why terminology matters.
“If we frame it as weight-loss medication, people will say, well, I’m not losing weight, so it’s not working any more. The challenge is to ensure people understand that the role is now maintenance. Even with the best medications we have available today, when their weight stabilises, it may not be where they want to be.”
The conversation around GLP-1s needs to be nuanced, he says.
“Obesity medications may not necessarily make somebody thin. They definitely won’t make people happy. But they will significantly improve somebody’s health and often their quality of life long term.”
Obesity care is not just about writing a prescription for somebody, he says. It also involves helping people navigate any side effects and managing their expectations.
“These are obesity medications. They’re definitely not skinny jabs, they’re definitely not Hollywood’s worst-kept secret, or all these other euphemisms. These medications need to be for people with obesity, not for somebody who wants to lose weight in the short term, or, God forbid, somebody who is living with an eating disorder.”
‘Very often the fake Ozempic pens contain sterile water, if it’s even sterile. There’s either nothing in them or they’re dangerously toxic’
— Tom Murray, pharmacist
With optimism and excitement about the widening array of available treatments, there has been some misrepresentation, Crotty says, “and perhaps some people taking advantage of the situation, too”.
Indeed, online fat-shaming can be driven by scurrilous entities seeking to profit from the advent of GLP-1s by promoting and selling counterfeits.
In August, responding to the surging rate of fake-drug seizures by the Health Products Regulatory Authority, the Irish Pharmacy Union urged the public against buying products marketed as obesity medicines from unverified websites and taking them without medical supervision.
“We have absolutely no way of checking what’s in these products,” says Tom Murray, a Donegal-based community pharmacist and the president of the union.
“Very often the fake Ozempic pens contain sterile water, if it’s even sterile. There’s either nothing in them or they’re dangerously toxic,” he says.
“There is some evidence of beauticians and the cosmetic industry supplying what they believe are GLP-1s, but they actually have no idea what they are.”
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Social pressure, combined with nefarious use of online advertising algorithms, has enabled unverified operators to create a market out of vulnerable people, says Murray. Typically this target market comprises patients who wouldn’t satisfy the body mass index (BMI) and medical conditions required to obtain medicines such as Mounjaro and Wegovy on prescription from their GP.
But it is also possible that some obese people have been motivated by “a small saving” to try the black market because obesity medicines – the price of which is set by the manufacturers – cost patients hundreds of euro a month out of their own pockets.
At present, the only GLP-1 that is reimbursable for obesity under the medical card and Drugs Payment Scheme is Saxenda (liraglutide), and even here the reimbursement is only available under extremely restrictive conditions.
Applications have been submitted for Mounjaro and Wegovy. However, Prof Michael Barry, who assesses the value-for-money of medicines in his role as director of the National Centre for Pharmacoeconomics, has warned that it would be “unaffordable” for the State to cover the cost of these drugs for all patients who would potentially benefit from them. This difficulty is not unique to Ireland.
Doctors hope that as more treatments become available – including oral pills, the next potential game-changer – the costs will come down. But this is far from guaranteed. In the meantime, many if not most obese people are effectively excluded from the health gains that GLP-1s can bring.
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“If you have diabetes, you can access a weekly injectable medication [and be reimbursed], but if you have obesity, you can’t. So again, it’s that idea that diabetes is a medical problem, but obesity is still framed as a lack of willpower, lack of motivation, personal responsibility,” says Crotty.
“And I say the same stuff every day, but telling somebody with obesity to eat less and move more is a bit like telling somebody with depression to cheer up. It’s a lovely idea, but it’s a gross oversimplification that minimises how complicated this is.”
Patients on GLP-1s who sustain their weight loss are often able to reduce their intake of other medications, says Treacy.
“They’re not on very strong painkillers any more for lower back pain or they’re on half the dose for blood pressure or they’re on half the dose for statins,” she says.
“That’s the essence of obesity treatment. It’s not about numbers on a scale, it’s about the health gains. And I know that’s been said so many times, but that really is the truth.”
