A seven-year-old boy in the United Kingdom was evaluated for a possible brain tumor after developing concerning symptoms. Detailed medical investigations later confirmed that the condition was vitamin D toxicity caused by an overdose of supplements.
The seven-year-old boy, Roo, presented with fatigue, unexplained weight loss, excessive thirst, and weakness. These symptoms are commonly associated with multiple serious conditions, which led clinicians to initially suspect a neurological disorder.
Roo was prescribed a high-dose course of vitamin D3 drops for 12 weeks in December 2024 to help relieve severe leg pain. This followed his referral to pediatric specialists at Crosshouse Hospital near his home in Kilmarnock, Ayrshire.
Initial blood investigations indicated that he was generally healthy, with the only finding being a mildly reduced vitamin D level. To correct this, he was started on vitamin D3 supplements, also known as cholecalciferol, aimed at increasing his blood levels.
In the weeks that followed, he began to experience increased drowsiness and a noticeable loss of appetite.
As reported by BBC, his mother, Carys Hobbs-Sargeant told that he started losing weight and began drinking excessive amounts of water, “as if he were extremely dehydrated.”
He lost more than 10% of his body weight over that six weeks. He had these huge baggy eyes and he was so tired and he just couldn't eat.
Carys Hobbs-Sargeant, Roo's mother
At his follow-up visit with the pediatrician, Roo was immediately admitted to the hospital. Such early signs of vitamin D toxicity can often be non-specific, delaying accurate diagnosis.
Initial blood investigations revealed that Roo had developed acute kidney injury, with significant dehydration affecting his kidneys, prompting doctors to investigate the underlying cause.
He became hypercalcemic, and they were very concerned that his calcium was so high in his blood. They were looking at whether it was a brain tumor, and we were sort of gearing up for him to have an MRI of his brain.
Carys Hobbs-Sargeant, Roo's mother
At that stage, the prescribed vitamin D was not suspected, as he had completed only about two-thirds of the recommended treatment course.
Further clinical assessment and laboratory findings revealed elevated vitamin D levels and hypercalcemia. This confirmed the diagnosis of hypervitaminosis D. High calcium levels in the blood are a key indicator of vitamin D toxicity and explain many of the child’s symptoms.
As reported by BBC, Roo’s unusual case was also assessed by specialists at the Royal Hospital for Children in Glasgow, and a phone discussion with an endocrinologist there helped identify the underlying issue. During the conversation, the endocrinologist mentioned that a colleague in Manchester had inquired about cases linked to a “defective batch” of vitamin D3.
We flipped from it was his body doing something weird to he's essentially been poisoned by this bad batch.
Carys Hobbs-Sargeant, Roo's mother
Using the batch details provided, Roo’s medical team cross-checked them with the bottle he was still using for his daily doses.
You felt relieved and lucky and angry all at the same time that it wasn't cancer, but it was something that had happened to him. It's poisoning, essentially.
Carys Hobbs-Sargeant, Roo's mother
The toxicity was linked to vitamin D3 supplement drops that were reportedly more concentrated than labeled. The child received doses significantly higher than prescribed due to this formulation error.
The defective batches were recalled by the Food Standards Agency (FSA) on 9 January. However, Food Standards Scotland (FSS), which handled the recall in Scotland, reported that the alert did not reach the appropriate departments.
The investigation further revealed that the pharmacy in Ayrshire which dispensed the drops did not identify the manufacturer’s recall email until almost three months after it had been issued.
In contrast, a medicines alert from the Medicines and Healthcare products Regulatory Agency (MHRA) would have been sent to the pharmacy’s high-priority clinical inbox and was expected to be reviewed without delay.
As reported by BBC, TriOn Pharma, the manufacturer of the drops, stated that it initiated an immediate recall and informed both the Food Standards Agency (FSA) and the Medicines and Healthcare products Regulatory Agency (MHRA) in accordance with regulatory requirements after identifying the issue.
Recall notifications were issued to all direct customers through established channels for onward communication across the supply chain. We continue to work with authorities to support patient safety.
TriOn Pharma
It took nearly a year for Roo’s vitamin D levels to return to a safe range, and according to Carys, the long-term effects remain uncertain.
This case underscores the importance of strict quality control in pharmaceutical and nutritional supplements. It also highlights the need for careful dosing and monitoring, especially in pediatric patients receiving high-dose vitamin therapy.
(Rh/SS)
