Falsified versions of Mounjaro pens have been supplied through an online pharmacy in the UK, the Medicines and Healthcare products Regulatory Agency (MHRA) has revealed.
It said the fake weight loss jabs were dispensed by The Private Pharmacy Clinic, based in Birmingham, and that five affected pens have been discovered so far.
“The issue was identified due to faults with the pens, where in all but one case the dose knob came off while in use,” it added.
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The MHRA said all Mounjaro KwikPen 15mg products with the batch number D873576 are falsified, and told healthcare professionals to “quarantine all remaining stock that has the affected dose and batch number” and return it to their supplier.
The batch number is “legitimate” for genuine Mounjaro KwikPen 7.5mg, it noted, and pens “at this strength are not impacted”.
The regulator added that it is “likely that the substance in the pens is tirzepatide”, the drug sold under the brand name Mounjaro, but the jabs “are not of the quality and safety standards of legitimate pens and are not safe to use”.
“Serious concerns”
The General Pharmaceutical Council (GPhC) last week issued an enforcement notice against The Private Pharmacy Clinic stating that it “must not obtain, sell or supply any prescription-only medicines or medical devices”.
The pharmacy has not met regulatory standards “in consecutive inspections”, it said, and “cannot show that restricted activities have always had the required oversight by a responsible pharmacist”.
It added that there is evidence indicating that the pharmacy “has not taken adequate or appropriate action to minimise risks to patients when there have been concerns raised about the quality of medicines”.
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“This means there are serious concerns about the pharmacy’s ability to operate safely and effectively,” the GPhC said. “The concerns are ongoing, and patients and members of the public continue to use the services of the pharmacy.”
“It is therefore necessary to impose the condition with immediate effect to protect the health, wellbeing and safety of patients and members of the public.”
C+D has approached The Private Pharmacy Clinic for comment.
Read more: Don’t rely on GPs for NHS weight loss jabs, NPA urges
It comes after new data revealed that the number of fake weight loss jabs seized by the UK’s medicines regulator soared in 2025.
Figures obtained by online pharmacy Quick Meds found that of the 6,526 weight loss jabs seized between 2023 and last year, a staggering 5,851 were confiscated in 2025 alone.
