Slimmers are in a frenzy to obtain a potent new weight loss injection referred to as the ‘Godzilla’ of slimming jabs, as concerns rise over the increasing cost of Mounjaro.

Preliminary studies of the drug, retatrutide, indicate that it can enable individuals to lose 25% of their body weight within a year, nearly twice as effective as the widely known Ozempic.

Unlike other slimming injections, the jab, also manufactured by Eli Lilly, not only suppresses appetite but also speeds up metabolism.

Because it targets three hormones involved in eating and weight regulation, it has been nicknamed ‘triple G’.

The once-weekly injection is still in clinical trials, with phase three results not expected until 2026. 

Yet social media users are already claiming to have sourced the drug on the black market, boasting of losing more than three stone in just months.

In their desperation, some have turned to online forums to seek alternative sources. One Reddit user expressed, ‘I’m considering switching to the black market for reta. Eli Lilly is leaving me no choice. I can’t afford the £300 cost [of Mounjaro].’

Another admitted: ‘Seeing a lot on TikTok about retatrutide, especially bodybuilders using it to get ripped.’

A TikTok user already claiming to inject it, added: ‘Two years from now, nobody will be using Mounjaro anymore.’

This rush occurs after Eli Lilly announced that in the UK, from September, the price of Mounjaro would significantly increase, with the highest dosage rising 170 percent from £122 to £330 monthly.

Even moderate doses like 5mg will nearly double in price to £180. The injection is currently prescribed to approximately 90 percent of Britons who use weight-loss jabs.

Health experts have urged people not to be tempted by unapproved supplies of retatrutide, warning that most are counterfeit and could be dangerous.

Dr Helen Wall said: ‘The issue is, we don’t really know what the risks are and we don’t know the dosing either.

‘It’s certainly not just a stronger version of Ozempic or Mounjaro. It’s working on a different pathway, so that needs exploration in terms of safety and side effects.’

Eli Lilly also issued a stark warning. A spokesperson said: ‘Retatrutide is an investigational molecule that Lilly is studying for the treatment of obesity—it is in phase 3 clinical trials and is not available to patients outside of these trials.

‘Any product falsely representing itself as a Lilly investigational product not yet approved… may expose patients to potentially serious health risks.’

Pharmacists say the looming Mounjaro price hike could drive more people towards the black market. 

Robert Bradshaw, superintendent pharmacist at Oxford Online Pharmacy, told the Mail: ‘The bigger concern is that this sharp price increase could fuel the expansion of the weight-loss jab black market.

‘Unlicensed and illegal jabs have circulated since weight-loss injections first became popular, often being sold via social media and by unlicensed individuals with no regulation.’

Last year this website revealed counterfeit versions of the drug were already on sale in Britain for as little as £2 a shot.

Chinese firms were even offering samples for 80p a dose, labelled as ‘research only’ and ‘not for human consumption’ in a bid to dodge regulators.

Trial results so far have shown striking weight-loss figures. 

In one study, women on retatrutide lost an average of 28.5 per cent of their body weight in 48 weeks, while men lost 21.2 per cent.

More obese participants lost 26.5 per cent, and unusually every single participant shed at least five per cent of their body weight. 

Side effects were similar to other GLP-1 drugs, including nausea, diarrhoea and constipation.

By comparison, Ozempic typically results in up to 15 per cent weight loss over 68 weeks, while Mounjaro has been shown to deliver up to 22.5 per cent over 72 weeks.

Despite the hype, experts stress that retatrutide remains experimental and years away from approval. 

Until then, desperate patients sourcing it online may be risking far more than their waistlines.