Lithium is one of the most effective psychotropic drugs we have, but it isunderused because of its low therapeutic index, the need for regular bloodtests and perceptions about its adverse effects, including renal problems.The last include urinary concentration deficits and diabetes insipidus,chronic kidney disease (including renal failure), nephrotic syndrome,hypercalcaemia, hyperparathyroidism and distal tubular acidosis. Thisarticle reviews these adverse effects with special emphasis on theirmanagement.