I’m a weight-loss doctor – how to survive the Mounjaro price hike

News that weight-loss jab Mounjaro has become the latest casualty of global politics would have come as a disappointment to patients across the UK. 

Eli Lilly, its US-based manufacturer, recently confirmed that the price of the drug will rise steeply for British patients from September 1 as a result of a White House push to raise drug prices in Europe so they can be lowered in the US.

As a doctor, I know this will be worrying for the estimated 1.5million people who buy the injection privately in the UK. 

The jab is prescribed to around 90 per cent of those using weight-loss injections here, and at the highest dose – 15mg – the monthly cost will rocket from £122 to £330, a rise of 170 per cent. 

Even mid-range doses, such as the 5mg pen, will jump from about £92 to £180. 

While some retailers may be able to negotiate discounts, patients are understandably anxious. In recent days I’ve been contacted by many who fear they’ll have to give up the drug completely, or that they’ll put back on the weight they’ve worked so hard to lose.

But there are ways forward. Whether you’re already on Mounjaro or considering starting it, it’s important to know there are options. With this in mind, here’s how to keep using the drug safely, and the alternatives available if the new prices prove unaffordable…

Should I stop taking Mounjaro?  

You should always consult your own doctor or prescriber first to discuss the best next steps. That said, my advice is simple: if Mounjaro is working well for you, do your best to stay on it. 

Most patients don’t need the maximum 15mg dose – in fact, the majority achieve the desired effect at around 10mg. 

This means that while prices are rising sharply, the steepest hike may not apply to you.

If you genuinely can’t afford Mounjaro but want to remain on it because other weight-loss treatments haven’t worked, one option is to dial down the dose. 

For example, if you have a 10mg pen, you could halve the clicks and give yourself 5mg instead. This approach, however, has limitations. 

The pen must still be used before its expiry date, and lowering your dose may lead to some weight regain, as the amount of appetite-suppressing chemical in your system will be reduced.

Wegovy, produced by Novo Nordisk, is a safe alternative if you want to stay on weight-loss injections. It is similar to the way Mounjaro works – but not identical. 

If you still choose to do that, you must make sure you have a very good exercise regime in place. These drugs are not a replacement for a healthy lifestyle.

The most important thing is not to go completely cold turkey. Multiple studies have demonstrated that if you come off these drugs abruptly you will see weight gain, and it is likely that this weight will be fat rather than muscle.

But isn’t Wegovy an inferior drug to Mounjaro? 

In clinical trials, Mounjaro has been shown to deliver the greatest weight loss of any licensed drug, with patients losing on average up to 22.5 per cent of their body weight over 72 weeks at the highest dose.

By comparison, Wegovy patients lose up to 17.5 per cent over the same period on the full 2.4mg dose.

But it’s important to remember that very few people are actually being prescribed the maximum Mounjaro dose. Many of my Mounjaro patients actually are already weaning down to smaller doses as they have reached the desired weight-loss effects at 10mg and are now aiming to maintain this. 

There are also benefits of Wegovy that go beyond just weight loss. There is very clear evidence that it also protects your heart, kidneys and brain from the effects of excess weight as well as protecting against other diseases. 

We don’t have that evidence yet for Mounjaro. 

So although you may not see weight loss as dramatic as Mounjaro on Wegovy, I would say you’re actually getting a superior product.  

How do I make the switch to Wegovy? 

Before taking Wegovy – which is also sold as Ozempic for diabetes treatment – you would need to completely stop Mounjaro for a few weeks before beginning Wegovy. 

This is because both medications affect the same hormones and you should not be double dosing. 

During this period, some weight gain is likely but it should be very modest given the short time off the medication. 

Exactly how long – days or a handful of weeks – you have to leave between finishing Mounjaro and starting Wegovy is a decision that is up to your prescriber. 

Pharmaceutical companies have very strict guidelines on how to use the medications, so it is important to follow the instructions given by your prescriber.

How do I know what dose of Wegovy to take? 

While Mounjaro weekly doses typically start at 2.5mg and increase in 2.5mg steps – 5mg, 7.5mg, up to 15mg – Wegovy usually starts at 0.25mg.

Like Mounjaro, this is titrated up over a period of several months to a maintenance dose of 2.4mg weekly.

You, of course, must check with your prescriber first about what switching to Wegovy, and working your way up the doses, will look like. 

You might think if you’re on the maximum 15mg dose of Mounjaro you should be able to switch straight to 2.4mg of Wegovy, but I wouldn’t do that for any of my patients. 

I will be looking at a maximum switch to 1mg of Wegovy and put them through a more rapid titration schedule – moving them up the doses slightly more quickly. 

I wouldn’t go straight to the top dose because the two medications work slightly differently so the side-effects will vary.

You’ll likely be put on a lower equivalent dose of Wegovy and have to put up with some of the food noise for a while, before you start increasing dosage. 

But if you’re on 2.5mg of Mounjaro and you’re just starting out on the drug your prescriber will likely switch you to 0.25mg of Wegovy.  

How do side effects differ on the two jabs?

Wegovy mimics one hormone released by the body after a meal, to flip one appetite switch in the brain. Mounjaro, meanwhile, flips two.

So, we would expect more side effects from Mounjaro than Wegovy. So if you’re already tolerating Mounjaro well, you’ll likely tolerate Wegovy. 

But you don’t necessarily get the same side-effects if you’ve been on both drugs. It does vary from person to person. Gastrointestinal issues, such as abdominal pain, nausea, diarrhoea and constipation, are common among both. 

This year, the Medicines and Healthcare products Regulatory Agency (MHRA) warned that weight-loss injections including Mounjaro and Wegovy could make the oral contraceptive pill less effective. 

The medicines regulator said it had received more than 40 reports relating to pregnancy among women on the drugs.

This is not unexpected because the way the medication affects the contraceptive pill is as much to do with rapid weight loss itself. We have to make patients aware that losing significant weight can make them more fertile. 

Do I have other fat jab options aside from Wegovy?

If you are getting your desired weight-loss affect on a low dose of Mounjaro, it is worth also considering liraglutide.   

Sold under the brand name Saxenda, the daily self-administered jab is another weight-loss treatment already available on the NHS and privately. 

It works in a similar way to Mounjaro and Wegovy by altering the body’s metabolism, making people feel fuller and less hungry. It is also much cheaper because it is virtually off patent now.

This means other companies can produce and sell versions of the same drug without needing to pay licensing fees to the original manufacturer, therefore reducing the price. 

I’ve seen some patients who are very rapid responders to Mounjaro and these patients do respond really well to low doses of Saxenda. 

• Professor David Strain is an Associate Professor of Cardiometabolic Health at the University of Exeter, an honorary consultant in medicine for older adults and the chair of the British Medical Association’s Board of Science