Retitration After Abrupt Lithium Discontinuation
For a patient who abruptly stopped 900mg lithium for two weeks, restart at the full previous dose of 900mg immediately, as the two-week gap represents a complete washout period (elimination half-life 18-36 hours) and the patient faces extremely high relapse risk that outweighs any retitration concerns. 1, 2, 3
Rationale for Immediate Full-Dose Restart
The critical window for rebound mania is highest in the first weeks to 6 months after lithium discontinuation, making rapid re-establishment of therapeutic levels the priority 4, 2, 5
After two weeks off lithium (approximately 5-10 half-lives), the patient has zero residual drug and is at >90% risk of relapse based on non-adherence data 2
Abrupt discontinuation creates a rebound effect with higher relapse risk than predicted by the natural disease course alone, particularly for manic episodes 5, 6
Practical Implementation
Resume 900mg daily (the previous stable dose) immediately without gradual titration 1, 3
Use once-daily evening dosing or twice-daily dosing depending on formulation (sustained-release allows once-daily) 3
Check serum lithium level at 5-7 days (approaching steady-state), then again at 12 hours post-dose once stable 7, 3
Target therapeutic range of 0.6-0.8 mmol/L for standard formulations, or 0.8-1.0 mmol/L for sustained-release preparations 3
Critical Monitoring in First Month
Monitor twice weekly for the first 2-4 weeks given the high-risk period post-discontinuation and need to confirm therapeutic levels quickly 2
Watch for early toxicity signs (tremor, nausea, diarrhea, polyuria) even before steady-state is reached 7
Assess renal function, thyroid function, and electrolytes at baseline restart since the patient was previously on chronic therapy 7
Key Clinical Caveats
Do not use gradual retitration – this is only appropriate when tapering DOWN, not restarting after discontinuation 1
The tapering guidelines (10% per week reduction) apply to discontinuation, not reinitiation 1
Avoid NSAIDs, ACE inhibitors, and diuretics during this restart period as they increase lithium levels and toxicity risk 2, 6
If the patient has developed renal impairment during the off period, dose adjustment may be needed, but this should be guided by levels, not prophylactic dose reduction 8, 3
Addressing the Underlying Non-Adherence
This two-week gap represents treatment failure requiring immediate intervention beyond just restarting medication 2
Re-educate on the 92% vs 37.5% relapse rates (non-compliant vs compliant) to emphasize adherence importance 2
Consider whether lithium remains appropriate if adherence cannot be reliably achieved – alternative mood stabilizers or long-acting injectable antipsychotics may be safer 2, 6
The regimen that stabilized acute symptoms must be maintained for 12-24 months minimum, with many patients requiring lifelong therapy 4, 2