Which parameter is NOT routinely monitored in patients taking lithium?

• A. Renal function
• B. Thyroid function
• C. Serum lithium levels
• D. Cardiac function

Answer: (D)

Regular lithium management focuses on preventing toxicity by watching how the drug interacts with organs most affected and by tracking its levels in the blood. Because lithium is cleared by the kidneys, renal function is routinely checked to catch any emerging nephrotoxicity or changes in kidney concentration ability. Lithium can also affect the thyroid, so thyroid tests are performed to detect hypothyroidism early. Serum lithium levels are measured regularly to keep the drug within its therapeutic window and to identify early signs of toxicity. Cardiac function is not part of routine monitoring for most patients on lithium; it’s checked only if there are cardiac symptoms or specific risk factors, since heart effects are not a common, standard concern with typical lithium therapy.