When seven-year-old Rue suddenly became unwell last year – losing weight and drinking a lot of water – his doctors and parents worried he might have a brain tumor.
But an investigation found he was poisoned by an accidental overdose of vitamin D, which is prescribed to treat growing pains.
Roo’s vial of vitamin D3 drops was about seven times more concentrated than it should be and came from one of two bad batches distributed across the UK.
The dose caused Ruault acute kidney injury, and a leading expert told BBC News that he would have died had he completed the prescribed course of treatment.
Caris says Rue is still not fully recovered a year later [BBC]
Vitamin D is an important nutrient that regulates calcium and phosphate and maintains healthy bones, teeth and muscles. It is used as an over-the-counter supplement by millions of adults.
However, higher doses of vitamin D prescribed by doctors are still classified as food supplements and are not regulated by the medicines regulator MHRA.
In contrast, vitamins and food supplements are monitored by the Food Standards Agency.
The MHRA said it worked with the FSA to ensure public safety.
But the medicines regulator should consider changing the way vitamin supplements are regulated, a leading expert has told BBC News.
Roo admitted to hospital after taking vitamin D drops [Carys Hobbs-Sargeant]
In December 2024, Roo underwent 12 weeks of high-dose vitamin D3 drops in an attempt to relieve severe pain in his legs.
He was previously referred to a pediatrician at Crosshouse Hospital near his home in Kilmarnock, Ayrshire.
Blood tests showed he was in good health except for a slightly lower than normal vitamin D level.
He took a supplement containing vitamin D3 (also called cholecalciferol) to increase vitamin D3 levels in his blood.
Over the next few weeks, Rue became lethargic and lost her appetite.
His mother, Carys Hobbs-Sargeant, said he began to lose weight and started drinking water “like he was in the desert.”
Throughout January, Roo suffered from vomiting and had difficulty eating.
“He was very sick,” Caris said.
“In those six weeks he lost more than 10 per cent of his weight. His eyes were huge, he had huge bags under his eyes and he was so tired he couldn’t eat.”
When Roo saw the pediatrician again, he was immediately taken to the hospital.
Vitamin D3 drops are used to increase levels in the blood [BBC]
Preliminary blood tests showed Rue was suffering from acute kidney injury, in which his kidneys were severely dehydrated, so doctors began looking for the cause.
They were not initially concerned about the vitamin D prescription because he was only completing two-thirds of the recommended dose course.
But his condition continued to worsen.
“He had hypercalcemia and they were very concerned that the calcium levels in his blood were too high,” said his mother, Caris.
“They’re checking to see if it’s a brain tumor and we’re getting ready to do an MRI on his brain.”
The team at the Royal Children’s Hospital in Glasgow were also reviewing Rouault’s mysterious case, and a chance phone call with an endocrinologist there provided the missing piece of the puzzle.
A colleague in Manchester asked him if he had ever seen a “bad batch” of vitamin D3.
With details from that batch, Roo’s team was able to cross-reference with the bottles he was still dripping from every day.
“We found out that his body was doing some weird things and he was basically being poisoned by this bad product,” Kallis said.
“You feel relieved, lucky and angry because it’s not cancer, it’s what happened to him. Essentially, it’s poisoning.”
One of Roo’s bottles of drops matched one of two batches of defective Aactive D3 supplements produced by TriOn Pharma and distributed across the UK.
These droplets are seven times more concentrated than they should be.
The Food Standards Agency (FSA) recalled the faulty batches on January 9, but Food Standards Scotland (FSS), which is responsible for recalls north of the border, said the alert had not been communicated to the correct department.
The investigation also found that the Ayrshire pharmacy that dispensed the drops did not receive a recall email from the manufacturer until almost three months after it was sent.
Medicines alerts from the MHRA will be sent to the pharmacy’s high priority clinical inbox – and should then be read immediately.
Professor Stuart Ralston said Roo was lucky not to have completed the required course [BBC]
Professor Stuart Ralston of the University of Edinburgh is the former Chairman of the MHRA Human Medicinal Products Committee. He said Roo’s shocking case showed why the MHRA should consider taking over regulation of vitamin supplements.
“It was estimated that the product contained seven times more vitamin D than he should be taking,” he said.
“I have never been in a situation like this in my 40-plus-year career.
“He was originally going to do a 12-week course. If he had done that the number would have been 3.5 million units, luckily he didn’t because if he had done that he would have died without a doubt.”
Roo’s GPs could receive an emergency alert if the supplement was regulated as a medicine, Ralston said.
The MHRA said the regulation of dietary supplements is the responsibility of the FSA and they will work together to ensure public safety.
The FSS said it works closely with the Food Standards Agency and local authorities to ensure product recalls are communicated effectively.
The Scottish Government told Caris it had raised regulatory and supplement recall concerns with the UK Department of Health and Social Care.
Kayan Khan takes supplements from the same brand [BBC]
A month before Roo started taking vitamin D3 drops, Kayan Khan from Sheffield also took the same brand of supplements.
Kayan, now 13, has multiple complex medical conditions, including chronic kidney disease, and was prescribed an eight-week course of vitamin D by his GP, in line with recommendations.
In February 2025, Kayon was admitted to Sheffield Hospital with high calcium levels and declining kidney function.
A letter to his mum Alaina from Sheffield Children’s NHS Foundation Trust said doctors had been working to control his calcium levels and found he was suffering from vitamin D toxicity “well beyond what would be expected from standard supplements”.
Alaina did not keep the bottle of vitamin drops, so the exact batch could not be confirmed, but the letter said a “reasonable explanation” for his toxic levels was an increased intake of vitamin D.
Although news of the FSA recall had been communicated to hospital doctors and local pharmacies, Alaina had not received it.
She said she only learned about the recall in April 2025.
Kayan’s kidney function has seriously deteriorated and, although he has now recovered slightly, a transplant may be needed in the future.
“As a parent, as a mother, I’m disappointed,” she said.
“I couldn’t help but feel that for eight weeks I had been slowly poisoning my son.”
Dr Jeff Perring, executive medical director at Sheffield Children’s NHS Foundation Trust, said its standard practice was to ask GPs to prescribe the medication, but they followed strict procedures for informing patients and families about recalls of directly prescribed medicines.
TriOn Pharma, the manufacturer of the drops, said it initiated a recall as soon as the problem was discovered and notified the FSA and MHRA as required.
“Notification of the recall has been issued to all direct customers through established channels for subsequent communication throughout the supply chain,” they said.
“We will continue to work with authorities to support patient safety.”
It took about a year for Roo’s vitamin D levels to return to a safe range [BBC]
It took about a year for Roo’s vitamin D levels to return to a safe range, and Carys said the long-term effects remain unclear.
“He went from being an outdoor forest school kid to someone who now needs a wheelchair to walk longer distances,” she said.
“He’s not immediately back to where he was before, he’s still dealing with it every day.”
