A patient on lithium presents with coarse tremor, cogwheel rigidity, confusion, and oliguria. Serum lithium is 2.8 mEq/L. The immediate priority in management is:

• A Reduce lithium dose and add propranolol for tremor
• B Administer IV sodium bicarbonate to alkalinise urine and enhance renal excretion
• C Stop lithium immediately and initiate haemodialysis ✓
• D IV saline hydration with thiazide diuretic to increase lithium excretion

Explanation

A serum lithium level of 2.8 mEq/L with neurological signs (coarse tremor, rigidity, confusion) and oliguria indicates severe lithium toxicity requiring immediate discontinuation of lithium and haemodialysis to rapidly lower serum levels. Haemodialysis is indicated when serum lithium exceeds 2.5 mEq/L with severe symptoms or renal impairment. Thiazide diuretics paradoxically increase lithium retention (not excretion), making option D harmful. IV saline restores sodium balance and promotes renal lithium excretion but is insufficient alone at this level of toxicity.

Reference: Kaplan & Sadock's Synopsis of Psychiatry, 11th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.