What is the recommended taper schedule for an adult patient with a history of bipolar disorder taking lithium (lithium) ER 300mg twice daily (bid)?

Lithium ER 300mg BID Taper Protocol

Lithium should be tapered gradually over weeks to months by reducing 10-25% of the current dose every 1-2 weeks, with close monitoring for rebound mania, as abrupt discontinuation can precipitate rapid mood destabilization in bipolar disorder. 1

Critical Safety Framework

• Never discontinue lithium abruptly, as this causes rebound worsening of manic symptoms and can lead to rapid relapse of bipolar disorder 1
• Gradual tapering is essential to allow underlying neuroadaptations time to resolve and minimize relapse risk 1
• The taper rate must be determined by the patient's tolerance and clinical stability, not a rigid predetermined schedule 2

Recommended Tapering Schedule

Initial Reduction (Weeks 1-2)

• Reduce from 300mg BID (600mg/day total) to 450mg/day (25% reduction) 2
• This can be achieved by taking 300mg in morning and 150mg in evening, or 225mg BID if that formulation is available 2

Subsequent Reductions (Every 1-2 Weeks)

• Continue reducing by 10-25% of the current dose (not the original dose) every 1-2 weeks 2
• For example: 450mg → 337.5mg (25% reduction) → 253mg → 190mg, with reductions becoming progressively smaller 2
• Each reduction should be a percentage of the previous dose to prevent disproportionately large final decrements 2

Extended Taper for Long-Term Users

• For patients on lithium for years (as is common in bipolar disorder), consider slowing to 10% reductions of the current dose per month rather than every 1-2 weeks 2
• The entire taper may require 6-12 months minimum, and potentially longer for patients on long-term therapy 2, 3

Monitoring Requirements

Clinical Monitoring

• Follow up at least monthly during the taper, with more frequent contact (every 1-2 weeks) during difficult phases 2
• Monitor specifically for return of manic or depressive symptoms, as mood symptoms may recur weeks to months after dose reductions 1
• Assess for withdrawal symptoms at each visit, though lithium withdrawal is primarily characterized by symptom relapse rather than physical withdrawal 1

Laboratory Monitoring

• Continue checking lithium levels periodically during the taper, particularly after dose reductions 4
• Monitor renal function (creatinine, BUN) and thyroid function (TSH) as lithium can cause chronic kidney disease and hypothyroidism even during tapering 4
• Be aware that clinical toxicity can occur even with "normal" lithium levels in patients with chronic kidney disease 4

Managing Relapse During Tapering

If Manic or Depressive Symptoms Return

• Pause the taper immediately and maintain the current dose for 4-6 weeks to assess symptom stability 2, 3
• If symptoms worsen significantly, consider returning to the previous higher dose temporarily 2, 3
• Once stabilized, attempt a smaller reduction (e.g., 10% instead of 25%) with longer intervals between reductions 2, 3

Adjunctive Strategies

• Consider maintaining or optimizing other mood stabilizers (e.g., valproate) or antipsychotics during the lithium taper if the patient is on combination therapy 1
• Integrate psychotherapy (particularly cognitive behavioral therapy) during the taper to support mood stability 2
• Patient education about early warning signs of relapse improves outcomes and engagement 2

Special Considerations for Bipolar Disorder

Prophylactic Efficacy

• Lithium has superior long-term prophylactic effects for both mania and depression in bipolar disorder compared to many alternatives 5
• The decision to taper should weigh lithium's proven mood-stabilizing benefits against side effects or patient preference 1, 5
• If tapering due to side effects rather than remission, ensure an alternative mood stabilizer is optimized before completing lithium discontinuation 1

Timing of Symptom Return

• Unlike medications for anxiety or ADHD, bipolar disorder symptoms may not return for weeks to months after lithium reduction 1
• Extended monitoring (3-6 months) after complete discontinuation is necessary to identify delayed relapse 1
• Patients discharged from inpatient settings during a taper require close outpatient follow-up as symptoms may emerge after discharge 1

Common Pitfalls to Avoid

• Do not use straight-line percentage reductions from the starting dose (e.g., reducing 150mg every 2 weeks), as this creates disproportionately large final decrements 2
• Do not abandon the patient if tapering is unsuccessful; maintain the therapeutic relationship and consider maintenance at a lower dose rather than forcing complete discontinuation 2, 3
• Do not make "cold referrals" to other clinicians during the taper without ensuring they have agreed to accept the patient's care 3
• Do not rush the taper; the goal is durability and prevention of relapse, not speed of discontinuation 2

When to Refer to Specialist

• Patients with unstable psychiatric comorbidities (e.g., active suicidal ideation, severe depression) should have specialist involvement during tapering 2
• History of rapid cycling or multiple prior relapses warrants psychiatry consultation before initiating taper 1
• If office-based tapering has been unsuccessful with previous attempts, refer to psychiatry 2