What adjustments can be made to the treatment plan for a 60-year-old patient with a pacemaker and ongoing anxiety, currently taking venlafaxine 150 mg, aripiprazole 5 mg, hydroxyzine PRN, and buspirone 30 mg BID?

Management of Anxiety in a 60-Year-Old Patient with Pacemaker

Increasing venlafaxine to 225 mg daily is the most appropriate next step for this patient with ongoing anxiety, as it has an ascending dose-response curve and is safe with a pacemaker at higher doses.

Current Medication Assessment

The patient is currently taking:

• Venlafaxine 150 mg daily
• Aripiprazole (Abilify) 5 mg daily
• Hydroxyzine PRN
• Buspirone 30 mg BID (60 mg total daily)

Recommended Medication Adjustment Strategy

Primary Recommendation: Optimize Venlafaxine

• Increase venlafaxine from 150 mg to 225 mg daily
• Rationale:
  • Venlafaxine has an ascending dose-response curve, with greater norepinephrine reuptake inhibition at higher doses 1
  • Doses up to 225 mg daily are generally well-tolerated with minimal blood pressure effects 1
  • Clinical trials have demonstrated efficacy at 75-225 mg daily for anxiety disorders 2
  • Venlafaxine has demonstrated efficacy in panic disorder and generalized anxiety disorder 3, 4

Secondary Options (if venlafaxine increase is ineffective after 4-6 weeks):

1. Consider quetiapine augmentation:

   • Start at 25 mg at bedtime
   • Titrate as needed up to 150 mg
   • Particularly useful for anxiety with insomnia 5
   • Less likely to cause extrapyramidal symptoms than other antipsychotics 5

2. Consider aripiprazole optimization:

   • Increase from current 5 mg to 10-15 mg daily
   • Third-generation antipsychotic with less risk of QT prolongation 5
   • Less likely to cause extrapyramidal symptoms 5

Special Considerations for Patient with Pacemaker

Medication Safety with Cardiac Devices

• Avoid medications with significant QT prolongation risk:

  • Citalopram and escitalopram should be avoided due to QT prolongation risk 5
  • Tricyclic antidepressants should be avoided due to cardiotoxic effects 5
  • Chlorpromazine should be avoided due to QT prolongation risk 5

• Safer options with pacemakers:

  • Venlafaxine has minimal effect on cardiac conduction at doses below 225 mg 1
  • Aripiprazole has lower risk of QT prolongation compared to other antipsychotics 5
  • Buspirone has no significant cardiac effects 5

Monitoring Recommendations

1. After venlafaxine increase:

   • Monitor blood pressure within 2 weeks (potential dose-dependent increase) 1
   • Assess for side effects: nausea, dizziness, sweating, insomnia 6
   • Evaluate anxiety response using standardized scales at 4 weeks

2. Cardiac monitoring:

   • ECG to check QTc interval at baseline and after any significant dose increase
   • Routine pacemaker checks as scheduled

Potential Pitfalls to Avoid

1. Avoid benzodiazepines for long-term use:

   • While effective for acute anxiety, they carry risks of dependence and falls, especially in a 60-year-old patient 5
   • May cause paradoxical agitation in some patients 5

2. Avoid abrupt discontinuation of venlafaxine:

   • Can cause significant discontinuation syndrome due to short half-life 1
   • If changes needed, taper gradually over several weeks

3. Medication interactions:

   • Monitor for serotonin syndrome with multiple serotonergic agents (venlafaxine, buspirone) 1
   • Avoid adding MAOIs due to serious risk of serotonin syndrome 1

Alternative Approaches if First-Line Strategy Fails

1. Consider SNRI switch:

   • Duloxetine 30-60 mg daily if venlafaxine is not tolerated
   • More balanced serotonin/norepinephrine reuptake inhibition 1

2. Non-pharmacological interventions:

   • Cognitive-behavioral therapy (CBT) has strong evidence for anxiety disorders
   • Combination of medication and CBT may be more effective than either alone 5

The patient's current regimen already includes multiple anxiolytics at moderate doses. Rather than adding another agent, optimizing the current medications (particularly venlafaxine) is the most appropriate next step for managing ongoing anxiety in this patient with a pacemaker.