Mechanism of Cholestyramine-Induced Metabolic Acidosis

Pathophysiological Mechanism

• The excess chloride from cholestyramine reduces the strong ion difference (SID), calculated as the difference between strong cations (primarily Na+) and strong anions (primarily Cl-), which directly lowers blood pH according to Stewart's approach 1

Clinical Presentation and Diagnosis

• Laboratory findings typically show decreased serum bicarbonate and elevated serum chloride, indicative of hyperchloremic metabolic acidosis 1

Prevention Strategies

• Consider alternative bile acid sequestrants in patients with pre-existing acid-base disorders 2