How long should atypical antipsychotics be continued after an adult patient reaches remission?

Duration of Atypical Antipsychotic Treatment After Remission in Adults

According to NICE and CANMAT guidelines, atypical antipsychotics should be continued for at least 12 months after achieving remission in adult patients with psychosis, with consideration for longer treatment in cases of recurrent illness. 1

Evidence-Based Recommendations for Duration of Treatment

Initial Treatment Period After Remission

• The World Health Organization (WHO) guidelines clearly state that antipsychotic treatment should be continued for at least 12 months after the beginning of remission 1
• This recommendation is based on evidence that discontinuation of antipsychotics significantly increases relapse risk starting from as early as 2 months after discontinuation 2

Factors Affecting Treatment Duration Decision

The decision to continue or discontinue treatment after the initial 12-month period should consider:

1. Number of previous episodes:

   • First episode: Consider discontinuation after 12 months if stable
   • Multiple episodes: Consider maintenance for at least 2 years or longer 3

2. Relapse risk factors:

   • Diagnosis of schizophrenia (vs. other psychotic disorders)
   • Longer duration of illness
   • Poor premorbid functioning 4

3. Medication-specific considerations:

   • Different atypicals may have different optimal maintenance durations
   • In bipolar disorder, risperidone may not provide additional benefit beyond 24 weeks, while olanzapine may continue to provide benefit 3

Discontinuation Approach

If discontinuation is considered after the minimum 12-month period:

• Gradual tapering is essential:

  • Reduce by approximately 25% of the most recent dose
  • Allow 3-6 months between dose reductions
  • Final doses before complete cessation may need to be as small as 1/40th of therapeutic dose 5
  • Abrupt discontinuation significantly increases relapse risk

• Close monitoring during and after discontinuation:

  • Monitor for at least 2-3 months after complete discontinuation
  • Highest risk of relapse occurs in the first 8-12 weeks after discontinuation 2

Important Considerations and Caveats

Risk-Benefit Assessment

• Benefits of continuation:

  • Significantly reduced relapse rates (47-57% reduction in relapse risk compared to discontinuation) 2
  • Maintenance of functional gains and symptom control

• Risks of continuation:

  • Weight gain (average 3.2kg over 52 weeks with continued treatment) 3
  • Metabolic syndrome
  • Other medication-specific side effects

Long-term Outcomes

• Even with careful discontinuation, approximately 60% of patients will experience relapse within 12-24 months of discontinuation 2
• However, 39-46% of patients who discontinue antipsychotics do not relapse within 12-24 months 2

Clinical Algorithm for Treatment Duration Decision

1. Minimum treatment period: Continue atypical antipsychotic for at least 12 months after achieving remission
2. At 12-month assessment:
   • If first episode with good functional recovery: Consider gradual tapering
   • If multiple episodes or poor functioning: Continue for at least 24 months
3. If discontinuing:
   • Implement very gradual tapering over months
   • Provide enhanced monitoring during tapering and for 3+ months after
4. If continuing beyond 24 months:
   • Reassess risk-benefit ratio at least annually
   • Consider lowest effective dose to minimize metabolic side effects

Remember that while guidelines recommend at least 12 months of treatment after remission, the decision about longer-term maintenance must balance relapse prevention against the metabolic and other risks of continued antipsychotic exposure.