What is the mechanism of action of lithium-induced polyuria?

Question

I was reading in my pharmacology textbook on lithium in treating bipolar disorder, and I was curious to know if there was any specific action lithium takes to produce symptoms such as polyuria and polydipsia. Any help would be great. Also, what is the most common way to monitor lithium levels in the body?

Answer 1

Lithium causes neprhogenic diabetes inspidus. ADH is a hormone that binds to receptors in the kidney tubule and prevents water loss. Lithium makes ADH ineffective at collecting tubule and water is lost.

Other drugs, metabolic distubances, and diseases that cause a loss of ADH effect are demeclocycline, hypokalemia, hypercalcemia and chronic kidney disease.