Understanding Vitamin D Toxicity: Signs and Risks

9. Dehydration

Polyuria, or frequent urination, occurs as the kidneys try to remove excess calcium from the bloodstream. Calcium also interferes with urine concentration. The risk of severe dehydration increases if the kidneys excrete large volumes of dilute urine.

Dry mouth, tea- or amber-colored urine, low blood pressure, headache, fatigue, and increased thirst are all signs of dehydration. Drinking water to replace losses in urine may prevent dehydration, but too much water can also cause an electrolyte imbalance.