Weight Loss Drugs Under Scrutiny: Side Effects Raise Fresh Legal and Medical Questions
The rise of weight loss drugs like Ozempic, Wegovy and Mounjaro has been nothing short of a phenomenon. Originally developed to treat type 2 diabetes, these medications have found a broader audience in recent years, particularly among people seeking fast, medically assisted weight loss.
Nevertheless, as uses of the medication surges, so too do concerns. A growing number of patients are reporting serious side effects, including pancreatitis, vision loss, blood clots and problems with hormonal contraception. These reports are prompting regulatory action, legal scrutiny and important questions around safety, informed consent and indeed, accountability.
A dramatic rise in usage of weight loss drugs
Current estimates suggest that over 1.5 million people in the UK are now taking weight loss drugs. The true number may be higher. Increasingly, individuals are sourcing these medications online or through unregulated social media channels, bypassing the usual healthcare safeguards.
In June, the NHS announced the wider rollout of Mounjaro, a drug developed to help manage blood sugar in diabetics but now licensed for use in people living with obesity. The move is part of a broader strategy to reduce obesity-related illnesses in the UK. However, it comes at a point when clinicians are raising concerns about the side effects they are seeing in their patients.
Mounting reports of harm and MHRA Study
The Medicines and Healthcare products Regulatory Agency (MHRA) has confirmed a sharp increase in the number of adverse reactions linked to weight loss drugs. In response, MHRA, the regulator has launched a study to assess whether new guidance is needed.
This review may lead to changes in how risks are presented to patients. Labels could be updated to reflect the severity or likelihood of particular side effects. For example, the current label on Ozempic lists the risk of pancreatitis as “uncommon” – a category which may not reflect the experiences now being reported.
Lawsuits in the US
In the US, manufacturers are already facing lawsuits. Some patients allege that they were not properly warned about the potential risks, particularly in relation to gastrointestinal damage and long-term complications. These claims are fuelling debate over where the responsibility lies when novel drugs enter the mainstream without sufficient long-term safety data.
What we know so far
So, what are the risks? Although side effects vary, several categories are beginning to emerge:
- Pancreatitis: Patients taking Mounjaro have reported cases of acute pancreatitis, a serious condition involving inflammation of the pancreas, which can cause intense abdominal pain and nausea.
- Contraceptive failure: In June, the MHRA issued a safety alert following reports of unintended pregnancies. Early studies suggest that weight loss drugs may interfere with the effectiveness of the contraceptive pill, possibly by affecting how medications are absorbed in the gut.
- Pregnancy complications: Alongside concerns around conception, there are also fears that use of these drugs during pregnancy could raise the risk of miscarriage or birth defects. Further research is urgently needed.
- Vision loss and blood clots: Ozempic and Wegovy users have also reported more serious systemic issues, including changes in vision and suspected clotting events, though links are still being studied.
It’s worth noting that these drugs were never originally developed for general weight loss. They were designed to treat diabetes under medical supervision, in tightly controlled circumstances. Now, with commercial demand growing rapidly, the full risk profile for people without diabetes is not yet fully understood.
Informed consent and clinical responsibility
As new side effects come to light, the principle of informed consent becomes central. Patients must be fully aware of the risks and alternatives before agreeing to start treatment. That includes the less common or longer-term side effects, even when they appear infrequently in clinical trials.
Clinicians have a legal and ethical duty to explain these risks clearly. If a doctor fails to provide enough information about a drug’s effects, or prescribes it without proper assessment, this may give rise to a claim in medical negligence.
Likewise, if a drug manufacturer fails to disclose emerging risks, or if product labels are misleading or incomplete, there may be grounds for a product liability claim.
The developing legal landscape
The law in this area is evolving quickly. As claims begin to emerge – particularly in the US – the courts will likely assess not just the actions of clinicians, but also those of manufacturers and regulators. The growing availability of these drugs through unofficial channels may also complicate accountability.
Anyone affected by side effects should seek legal advice. The cause of harm can often be difficult to trace, especially if several providers or products were involved. An experienced lawyer can help assess whether there are grounds for a claim, either under clinical negligence or product liability.
Where to go for help
If you have experienced serious side effects after taking a weight loss drug, or if you are concerned that you were not properly informed before starting treatment, it is important to seek professional guidance. You may be entitled to bring a claim, particularly if you were harmed due to insufficient warnings, poor medical advice or mislabelling.
At Taylor Hampton law firm we specialise in both medical negligence and product liability claims. Our team can talk through what happened with you, explain your options and advise on the best way forward. In some cases, we may be able to assist on a no win no fee basis.
For a confidential discussion, please get in touch with Anna Johnson who heads up our medical negligence team. We are here to help.
