A seven-year-old boy from Ayrshire survived a near-fatal episode of vitamin D poisoning after being given a supplement that was seven times stronger than it was supposed to be. His case has exposed critical flaws in how such products are regulated and how dangerous recalls are communicated.
In 2025, Roo’s parents watched in horror as their son began rapidly losing weight, drinking excessive amounts of water, and suffering persistent vomiting. His symptoms were so severe his family feared he had a brain tumour. Medical investigations, however, revealed the true cause: a toxic overdose of vitamin D3 drops, which had been originally prescribed for growing pains. The bottle was from a faulty batch, and experts believe that completing the full course would have been fatal. Roo suffered an acute kidney injury and faces potential long-term health effects.
A Potent and Lasting Poison
The incident underscores a dangerous misconception that vitamin supplements are inherently safe because the body excretes any excess. In reality, vitamin D is fat-soluble, meaning it can accumulate in the body’s tissues for weeks or even months. Toxicity, known as hypervitaminosis D, occurs when excessive intake leads to dangerously high levels of calcium in the blood—a condition called hypercalcaemia.
According to Professor Stuart Ralston, former chair of the Medicines and Healthcare products Regulatory Agency’s (MHRA) Commission on Human Medicines, the early signs are often a powerful thirst and frequent urination. This can progress to nausea, vomiting, and a loss of appetite. As the condition worsens, patients can experience muscle weakness, bone pain, and profound fatigue. In severe cases, like Roo’s, the high calcium levels disrupt brain function, leading to confusion, apathy, and what is often described as “brain fog.” Left untreated, severe hypercalcaemia can cause kidney damage, abnormal heart rhythms, and can be fatal.
The primary treatment is to stop all supplementation immediately. Doctors may administer intravenous fluids to aid hydration and use drugs like bisphosphonates to lower blood calcium levels. However, recovery largely depends on time, as the body slowly processes and eliminates the stored vitamin D.
An Essential Nutrient with Clear Limits
Vitamin D is crucial for bone health, and deficiency is a significant public health concern in the UK. During autumn and winter, sunlight is insufficient for the body to produce its own, leading the government to recommend that everyone consider a daily 10 microgram (mcg) supplement. Certain groups, including people from South Asian, Black African, and Caribbean backgrounds, those who are housebound, or who cover their skin outdoors, are at particularly high risk. Approximately one in five people in the UK has a diagnosed deficiency.
Yet the line between sufficient and toxic is distinct. For adults, the safe upper limit is generally considered 100 mcg (4,000 International Units) per day. For children aged 1-10, it is 50 mcg (2,000 IU), and for infants under one, 25 mcg (1,000 IU). Professor Ralston advises particular caution, stating he “would definitely be wary of anything more than 400 units.” While some high-strength supplements are available, the incident with Roo was caused not by misuse, but by a manufacturing error in a product meant for children.
Regulatory Gaps and a Failed Recall
The faulty product was identified as “Aactive D3 Drops” and “Aactive D3 Solution,” manufactured by TriOn Pharma. On 9 January 2025, the Food Standards Agency (FSA) issued a recall for two batches—LS23317 and LS23318—after tests found vitamin D3 concentrations far higher than stated on the label.
This recall, however, failed to reach key parties in time. In Scotland, Food Standards Scotland reported that the FSA’s alert was not promptly disseminated to the relevant departments. Crucially, the pharmacy that had dispensed Roo’s supplement did not see the manufacturer’s recall email until nearly three months after it was sent. This delay meant the dangerous product remained in a family’s medicine cabinet while a child was being poisoned by it.
This communication breakdown has intensified a debate about how such supplements are classified. Vitamin D is currently regulated as a food supplement, falling under the remit of the FSA. Professor Ralston argues that high-dose vitamins should be reclassified as medicines, regulated by the MHRA. “There’s no real distinction between the doses in supplements and medicines,” he warns, noting that an MHRA-led medicines alert would have been rapidly issued to every GP, hospital, and pharmacy, ensuring frontline medical staff were informed immediately.
Roo’s case is not isolated. Another child, Kayan, was admitted to Sheffield Children’s NHS Foundation Trust in February 2025 with elevated calcium levels and impaired kidney function from the same brand of supplement. His family also learned of the recall months later, and he may now require a kidney transplant. A teenager in England is also reported to have suffered toxicity from the product.