Lithium Tablet Splitting Guidelines

Critical Safety Considerations

Lithium toxicity is closely related to serum concentrations and can occur at doses close to therapeutic levels, with toxicity beginning at 1.5 mEq/L and serious toxicity at >2.0 mEq/L, emphasizing the need for precise dosing 1, 2
Inconsistent dosing from improperly split tablets makes therapeutic monitoring unreliable and potentially dangerous, highlighting the importance of proper tablet handling 1, 3

Patients with reduced kidney function (GFR < 60 ml/min/1.73 m²) require lower doses and more frequent monitoring, which should be achieved with appropriate tablet strengths rather than splitting 1
For patients with severe kidney impairment (GFR < 30 ml/min/1.73 m²), a 50% dose reduction is recommended, which should be achieved with lower-strength tablets 1
Elderly patients requiring lower doses (e.g., 150 mg/day starting dose) should use appropriately sized tablets rather than splitting 1