A new case study published in the Canadian Medical Association Journal (CMAJ) illustrates the risk of high doses of vitamin D supplements, which could cause kidney failure in some cases.
The case study, “Use of vitamin D drops leading to kidney failure in a 54-year-old man”, shows a case of a 54 year old man who was prescribed high doses of vitamin D and spent a holiday sunbathing developing significant kidney damage.The authors explained: “Calcium levels may get worse before getting better in patients even after cessation of supplements, as vitamin D is fat soluble.”
The case study
The 54 year old man returned from a trip to Southeast Asia where he spent a lot of time sunbathing. Tests showed increased levels of creatinine, which suggested kidney damage or malfunction.
Following referral to a kidney specialist, it was revealed that the patient had been prescribed high doses (eight drops per day) of Vitamin D by a naturopath
Over a two and a half year period, the patient, who did not have a history of bone loss or vitamin D deficiency, took between eight and twelve drops of vitamin D daily (8000-12 000 IU total). This caused very high levels of calcium in the blood, which left him with significant kidney damage.
Toxicity caused by Vitamin D supplements
Dr. Bourne Auguste, a Clinical Fellow in Home Dialysis at Toronto General Hospital and the University of Toronto, explained: “Although vitamin D toxicity is rare owing to a large therapeutic range, its widespread availability in various over-the-counter formulations may pose a substantial risk to uninformed patients.”
The risks of kidney failure
The authors commented: “Our experience informs us that patients and clinicians should be better informed about the risks regarding the unfettered use of vitamin D. Given new findings from the US Preventive Services Task Force, current Canadian guidelines regarding its use in low-risk individuals should be revisited.”