New examine reveals ‘secret’ weight reduction jab unintended effects together with sizzling flushes
New research suggests weight-loss jabs like Ozempic may cause secret side effects including hot flushes, chills, and irregular periods
Popular weight-loss injections could be triggering a cluster of hidden side effects(Image: Getty)
Diet fans have warned that popular weight-loss injections could be triggering a cluster of hidden side effects not officially listed by drug giants. Medications like Ozempic and Mounjaro, originally designed to tackle diabetes, have become widely used for shedding pounds fast by suppressing the appetite.
But while many users celebrate their disappearing waistline, the jabs are already known to cause nasty bouts of nausea and constipation. In the most extreme cases, they have even been linked to life-threatening organ damage.
A bombshell study has now uncovered a new wave of secret symptoms, including hot flushes, shivering chills and irregular periods.
Researchers from the University of Pennsylvania turned to the internet to find out what patients are really experiencing. They used AI to scan over five years of posts from nearly 70,000 Reddit users between 2019 and 2025.
Writing in the journal Nature Health, the team confirmed that common complaints like nausea (36.9 per cent) and vomiting (16.3 per cent) were rife. However, they stumbled upon a “notable” amount of unreported issues.
The study states: “Notably, reproductive symptoms, for example, menstrual irregularities and temperature-related complaints, for example, chills and hot flushes, emerged as unrecognized potential effects. These findings highlight patient concerns not well captured in current labelling or trials.”
Fatigue also ranked as the second most common complaint on the social media site, despite rarely being flagged in official clinical trials.
Experts believe the jabs, known as GLP-1 medications, might not be attacking hormones directly. Instead, the “shock” of rapid weight loss and a massive drop in calories could be sending the body’s internal thermostat and reproductive system into a tailspin.
Neil Sehgal, the study’s lead author, said: “We can’t say that GLP-1s are actually causing these symptoms. But nearly four per cent of the Reddit users in our sample reported menstrual irregularities, which would be even higher in a female-only sample. We think that’s a signal worth investigating.”
Professor Lyle Ungar added that while clinical trials find the “most dangerous” risks, they often miss what patients care about most.
He said: “We don’t really know yet whether what we’re seeing on Reddit reflects the experience of GLP-1 users globally, or whether it’s particular to the kind of person who posts on Reddit in the United States.”
The drugs work by targeting the hypothalamus – the part of the brain that acts as a control centre for hormones.
Dr Jena Shaw Tronieri said: “These drugs are thought to work by engaging part of the brain called the hypothalamus, which helps regulate a wide variety of hormones.
“That doesn’t mean the medications are necessarily causing these symptoms, but it could suggest that reports of menstrual changes and body temperature fluctuations are worth studying more systematically.”
With over 1.6 million Brits now estimated to be using jabs like Wegovy and Mounjaro, regulators are keeping a close watch.
Earlier this year, the UK’s MHRA watchdog issued warnings for semaglutide users regarding eye strokes and acute pancreatitis.
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