Switching from Aripiprazole to Lithium
When switching from aripiprazole to lithium, start lithium at 150-300 mg/day while gradually tapering aripiprazole over 2-4 weeks to minimize withdrawal symptoms and prevent mood destabilization. 1
Cross-Titration Protocol
Step 1: Initiate Lithium
- Begin lithium at 150 mg/day while continuing full dose of aripiprazole
- Target therapeutic lithium blood levels of 0.2-0.6 mEq/L for most patients
- For bipolar disorder, higher therapeutic ranges (0.6-1.2 mEq/L) may be needed
- Schedule first lithium level check after 5 days of consistent dosing
Step 2: Gradual Aripiprazole Taper
- Week 1: Continue full aripiprazole dose while establishing lithium
- Week 2: Reduce aripiprazole by 25% of original dose
- Week 3: Reduce aripiprazole by 50% of original dose
- Week 4: Reduce aripiprazole by 75% of original dose
- Week 5: Discontinue aripiprazole completely
Step 3: Lithium Dose Adjustment
- Titrate lithium dose based on:
- Clinical response
- Blood levels
- Tolerability
- Typical maintenance dosage: 300-900 mg/day for most patients
- Monitor lithium levels weekly during cross-titration, then monthly once stable
Monitoring Requirements
Baseline Tests (Before Starting Lithium)
- Complete blood count
- Comprehensive metabolic panel (especially renal function)
- Thyroid function tests
- Electrocardiogram (especially in patients >40 years or with cardiac history)
- Pregnancy test for women of childbearing potential
Ongoing Monitoring
- Lithium levels: Weekly during titration, then monthly for 3 months, then every 3-6 months
- Renal function: Every 3-6 months
- Thyroid function: Every 6-12 months
- Electrolytes (especially sodium): Every 3-6 months
Special Considerations
Potential Drug Interactions
- No clinically significant pharmacokinetic interactions between aripiprazole and lithium have been reported 2
- However, caution is warranted as rare cases of neuroleptic malignant syndrome have been reported with concomitant use 3
Safety Precautions
- Maintain adequate hydration during lithium therapy
- Avoid NSAIDs which can increase lithium levels
- Educate patient about lithium toxicity symptoms (tremor, confusion, ataxia, vomiting)
- Ensure patient understands the importance of regular blood tests
Clinical Effectiveness Considerations
- Some studies suggest lithium may be more effective than aripiprazole for acute mania 4
- Long-term studies comparing aripiprazole and lithium show similar effectiveness profiles but different side effect patterns 5
- Consider that combination therapy with both medications has shown effectiveness in bipolar disorder when monotherapy is insufficient 6
Potential Challenges and Solutions
Managing Withdrawal Symptoms
- If akathisia, insomnia or anxiety emerges during aripiprazole taper:
- Consider temporarily slowing the taper
- Short-term benzodiazepine may be used if clinically appropriate
Addressing Side Effect Transitions
- Aripiprazole side effects (akathisia, insomnia) typically resolve within 1-2 weeks of discontinuation
- Lithium side effects (tremor, polyuria, thirst) typically emerge within first few weeks
- Weight changes: Aripiprazole discontinuation may reduce weight gain risk, while lithium has variable effects on weight
Follow-up Schedule
- Weekly appointments during the first month of cross-titration
- Every 2 weeks during the second month
- Monthly thereafter until stable on lithium monotherapy
- More frequent monitoring for patients with history of rapid cycling or high suicide risk