You have likely heard of Ozempic and Wegovy, but did you know they’ve become so popular that there are supply issues with the medication – thought to last until late 2024?
A huge reason for the demand is because many people are using the medication for rapid and unnecessary weight loss. Although Wegovy is licensed for weight management on the NHS, Ozempic is a prescription-only medication designed to treat type 2 diabetes. As a result, the shortages have meant those with the condition have been unable to continue with treatment.
In March this year, NHS England announced that a new jab, Mounjaro, could instead be offered to people unable to access other types of injectables, known as GLP-1 RA medications. The new jab, also known as tirzapatide, is thought to be even more effective than semaglutide medications Ozempic and Wegovy.
But these medications aren’t right for everyone and can have extreme and dangerous side effects.
How do weight loss jabs work?
According to Dr Mark Vanderpump, a consultant endocrinologist at OneWelbeck, weight loss jabs work by mimicking hormones that support normal blood sugar levels.
‘Over twenty years ago hormone researchers discovered a hormone called GLP-1, which was known to promote insulin action and reduce blood sugar levels,’ he explains to Metro.co.uk.
‘A form of GLP-1 was found in large quantities in the saliva of a large venomous lizard who lives in the Arizona desert which is known to eat infrequently. This discovery allowed scientists to synthesise a mimic of GLP-1 which is injectable and lasted for a long time in the body.’
Is Mounjaro more effective than Ozempic and Wegovy?
‘Mounjaro (or tirzapatide) is the latest version of the injectables that increase the body’s production of insulin and decrease the glucose produced by the liver, thereby lowering blood glucose.
‘By also targeting the appetite centres of the brain, it creates a sense of fullness and has been shown to be a very effective weight loss drug,’ Dr Vanderpump says.
However, unlike other drugs, Mounjaro also mimics another hormone known as GIP (or gastric inhibitory polypeptide). The dual-target makes Mounjaro more effective than semaglutamine in aiding weight loss.
‘In one study those individuals who tolerated the highest dose (15mg weekly) lost an average of 15-20% of their body weight in 12-18 month, compared with 10-15% with semaglutide,’ adds Dr Vanderpump.
Who is eligible for Mounjaro?
‘Although currently licenced to treat people living with type 2 diabetes, it is has been shown to be a very effective weight loss drug in individuals with pre-diabetes or the metabolic syndrome – i.e. those with genetic markers of insulin resistance who have had a lifelong struggle with weight management,’ says the doctor.
However, a surge in demand for jabs as people pursue weight loss means that diabetics are going without medication. Not only does this put treatment plans in jeopardy, but it’s also harmful to people who do not have metabolic differences.
‘Mounjaro is not for people with normal or slightly above normal weight who desire further weight loss for cosmetic reasons,’ stresses Dr Vanderpump.
What are the side effects of Mounjaro?
‘Common side-effects are similar to those described with semaglutide, which include feeling sick and having indigestion, constipation and diarrhoea. Less common side effects are reported as gallstones and pancreatitis,’ he explains.
Long-term, the drugs have been compared to statins for the beneficial impact they can have on heart health in those with diabetes. However, studies in the cardiovascular benefits of Mounjaro are still ongoing.
While the main side effect of these drugs is weight loss, ‘any weight loss achieved is likely to be regained within two years of stopping the drug,’ notes Dr Vanderpump.
This is why the jabs, despite how they may seem, are not a magic pill. Instead, they may best be seen as a supportive tool for people with medical conditions to kickstart their health journey alongside lifestyle changes such as eating well and moving more.
Side effects of Mounjaro – at a glance
Short-term:
- Sickness and nausea
- Indigestion & heartburn
- Constipation
- Diarrhoea
- Headaches
- Injection site reactions (redness, bruising, tenderness, swelling)
- Gallstones and pancreatitis (in rare instances)
- Positive impacts on heart health (in some instances)
Long-term:
- Weight loss
- Muscle mass reduction
- Slower metabolism
- Insulin resistance
‘People being treated with tirzepatide (Mounjaro) or semaglutide (Ozempic/Wegovy) often describe a change in their relationship with food which allows their lifestyle efforts to be rewarded,’ he says.
But for others, the sickness and other side effects of these jabs may make lifestyle changes feel even harder, meaning people are not better able to look after their health once their medication ends.
There are also worries over how weight loss occurs. Research suggests that about 40% of the weight people lost when using Wegovy tended to be muscle mass, a hugely important part of our composition for regulating metabolism when off the drugs. The same is thought to be true of Mounjaro.
‘Your basal metabolic rate (BMR) is the number of calories you burn as your body performs every day life sustaining activities. Your BMR is largely determined by your total lean muscle mass, because lean mass requires a lot of energy to maintain. Having more muscle requires more energy to function and improves metabolism,’ explains personal trainer Sarah Campus.
According to PT and nutritional scientist Eleanor Heaton-Armstrong, in the long run, people with metabolic problems will be worse off for losing muscle. ‘A sharp decrease in muscle mass would definitely be a concern to anybody, but for the also highly inadvisable for anyone trying to regulate their metabolism or monitor insulin levels.
‘Muscular atrophy is something type 2 diabetes or pre-diabetic patients should try and avoid at all costs because of the adverse affect on their metabolic rate. Insulin resistance has a direct link to lipid accumulation and consequently to a defective metabolism – it’s a vicious circle.
‘Losing weight is supportive when it comes to managing and preventing type-2 diabetes, but the cost of weight loss with these jabs isn’t always worth it.’
These jabs don’t work for everyone, either. ‘It must also be remembered that up to 10-15% of people do not lose weight or who are unable to tolerate the drug. And it is not safe in pregnancy, so needs to be stopped six weeks prior to any pregnancy attempt. It is not known if it is safe in breastfeeding,’ adds Dr Vanderpump.
Can you get Mounjaro on the NHS?
Mounjaro can be prescribed within the UK to treat type 2 diabetes.
‘It is usually only prescribed when other medications have proved ineffective in managing diabetes, because of side effects or because of other medical conditions.
‘It is specifically targeted to those people living with diabetes who have a BMI more than 35. It is not licensed for people living with obesity without diabetes or those with pre-diabetes, however, it can be prescribed via a private prescription for those unable to access it via the NHS with the current cost approximately £150 per month,’ says Dr Vanderpump.
But before trying to get a prescription to Mounjaro, it’s important to think about whether it is right for you.
‘For people without medical conditions, these drugs work strongly in contention with the body’s natural processes and also run the risk of decreasing a person’s quality of life,’ reminds Heaton-Armstrong.
‘Even for those with diabetes, unless they are being strictly monitored by healthcare professionals, the risks are big. Losing weight whilst retaining muscle mass isn’t easy and can often more or less require an overhaul of an individual’s diet and exercise regime, something that is difficult even without the added complication of diabetes and drugs.’
Education, access to healthy foods, moving regularly and building and maintaining muscle mass are all vital and need to be looked at in conjunction with Mounjaro.
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