In the last few days, I have seen two patients who had serious complications due to vitamin D overdose, which is toxic to the human body. It was a reminder of how we treat supplements harshly and don’t feel the need to consult a doctor about how much to take and when to stop. Most importantly, never buy them without a doctor’s prescription.
We know vitamin D is fat soluble and important for muscle, immune system and cell growth but our needs can easily be met by sunlight. Supplementation is advised only in certain situations, that too for a certain period of time. Otherwise, we may suffer from hypervitaminosis. Serum levels greater than 100 ng/mL (nanograms per milliliter) are considered toxic levels.
I was shocked to see a 25-year-old man in the emergency room Vitamin D Overdose can cause kidney failure, confusion, severe muscle fatigue, dehydration and nausea. He had to be admitted to the ICU for at least a week. How did he get there?
He had been complaining of severe back pain and had gone to a neighborhood orthopedic for a checkup. A blood test showed that he was severely deficient and the doctor suggested giving him an injection, so that his vitamin D levels could rise faster.
The problem was that the orthopedics prescribed him an extraordinarily high dose of 600,000 units — an annual shot usually given to certain patients with severe conditions under close medical supervision — every week, for eight weeks. It was more than necessary. He had abnormally high levels of calcium in his blood, which narrowed the blood vessels in the kidneys, causing kidney failure. We put him on IV fluids, dialysis and steroids to keep all his parameters down.
We monitored her heart because high levels of calcium in the blood can sometimes cause arrhythmias or irregular heartbeats.
The second case was a 68-year-old woman, who complained of severe pain in muscles and joints. I asked her if she was on any medication during a routine evaluation. She told me she got vitamin D pills from a healthy corner of a pharmacy and had been taking them for eight months or so. She didn’t know whether she should ask her doctor for the appropriate dosage for her needs or stop taking vitamin D supplements after a certain period of time. Some brave people just keep popping pills without any intervention.
The recommended daily intake of vitamin D is 400 international units (IU) for children up to 12 months of age, 600 IU for people aged 1 to 70 years, and 800 IU for people over 70 years of age. A daily vitamin D intake of more than 100 micrograms (4,000 IU) is dangerous. Children between 1 and 10 years should consume no more than 50 micrograms (2,000 IU) per day. Infants under 12 months should consume no more than 25 micrograms (1,000 IU) per day.