Question: Lithium is widely used as long-term therapy for bipolar disorder. What are the clinically important adverse risks for patients on long-term lithium therapy?
Answer: According to one systematic review and meta-analysis of randomized controlled trials and observational studies (more than 385 studies included): “Lithium is associated with increased risk of reduced urinary concentrating ability, hypothyroidism,
hyperparathyroidism, and weight gain. There is little evidence for a clinically significant reduction in renal function in most patients, and the risk of end-stage renal failure is low. The risk of congenital malformations is uncertain; the
balance of risks should be considered before lithium is withdrawn during pregnancy. Because of the consistent finding of a high prevalence of hyperparathyroidism, calcium concentrations should be checked before and during treatment.” (McKnight RF et al. Lithium toxicity profile: a systematic review and meta-analysis. 2012 Lancet 379:721-728)