POLYURIA MAY BE CAUSED BY WHICH OF THE FOLLOWING

• A. Increased antidiuretic hormone secretion
• B. Lithium toxicity ✓
• C. Reduced serum sodium concentration
• D. Hypocalcaemia
• E. Hypoglycaemia

Polyuria, which refers to excessive urination and the production of abnormally large volumes of dilute urine, can be caused by various factors. One significant cause of polyuria is lithium toxicity. Lithium, commonly used in the treatment of mood disorders like bipolar disorder, can lead to nephrogenic diabetes insipidus, a condition characterized by the inability of the kidneys to concentrate urine properly. This results in increased urine output and polyuria.

In cases of lithium intoxication, as seen in patients who have taken excessive amounts of lithium or have high serum lithium levels, the kidneys may be affected, leading to impaired urinary concentrating ability and ultimately polyuria. The toxic effects of lithium on the kidneys can result in conditions like nephrogenic diabetes insipidus, contributing to polyuria as a symptom.