Is it safe to use propranolol (a beta-blocker) to manage akathisia in a patient with treatment-resistant bipolar disorder, currently taking lithium, Latuda (lurasidone), and Coreg (carvedilol, a beta-blocker)?

Managing Akathisia in a Patient on Carvedilol

Do not add propranolol to this patient's regimen—the combination of two beta-blockers (propranolol plus carvedilol) creates unnecessary risk of additive cardiovascular effects including bradycardia, hypotension, and heart block without clear evidence of superior akathisia control. 1

Primary Recommendation: Alternative Approaches

First-Line Alternative: Low-Dose Mirtazapine

Initiate mirtazapine 7.5 mg once daily at bedtime as the preferred alternative to propranolol for this patient. 2

• Mirtazapine demonstrates compelling evidence for therapeutic efficacy in antipsychotic-induced akathisia through its marked serotonin 5-HT2a receptor antagonism 2
• The 7.5 mg dose provides optimal 5-HT2a antagonism with minimal sedation compared to higher doses 2
• This approach avoids the cardiovascular complications of dual beta-blockade 2
• Response typically occurs within 3-7 days; if inadequate, increase to 15 mg once daily after one week 2

Second-Line Alternative: Benzodiazepines

If mirtazapine is contraindicated or ineffective:

• Add lorazepam 0.5-1 mg twice daily as needed for subjective distress 3
• Benzodiazepines provide symptomatic relief of the inner restlessness component of akathisia 3
• Use time-limited (days to weeks) to avoid tolerance and dependence 3

Third-Line Options

If both mirtazapine and benzodiazepines fail:

• Consider amantadine 100 mg twice daily or clonidine 0.1 mg twice daily 3
• These agents have weaker evidence but may provide benefit when first-line options are unsuccessful 3

Why Propranolol Is Problematic Here

Cardiovascular Risk with Dual Beta-Blockade

• Carvedilol is a non-selective beta-blocker with alpha-1 blocking properties already providing beta-adrenergic antagonism 1
• Adding propranolol creates redundant beta-blockade with cumulative risk of:
  • Severe bradycardia (heart rate <50 bpm)
  • Symptomatic hypotension
  • Heart block, particularly in patients with underlying conduction abnormalities
  • Worsening heart failure if carvedilol is prescribed for cardiac indications 1

Paradoxical Akathisia Risk

• Recent evidence suggests propranolol may paradoxically increase akathisia risk when combined with certain antipsychotics through CYP2D6 inhibition 4
• While this study focused on aripiprazole, the principle of drug-drug interactions raising antipsychotic levels applies to lurasidone as well 4
• Propranolol's CYP2D6 inhibitory activity can elevate antipsychotic plasma concentrations, potentially worsening akathisia 4

Addressing the Underlying Cause

Optimize Lurasidone Dosing

• Evaluate whether lurasidone dose can be reduced while maintaining mood stability 1
• The APA guideline suggests lowering the antipsychotic dose as a primary strategy for akathisia management 1
• Consider reducing lurasidone by 25% (e.g., from 80 mg to 60 mg, or from 60 mg to 40 mg) and reassess akathisia severity after one week 1

Consider Antipsychotic Switch

• If dose reduction destabilizes mood, switching to another antipsychotic with lower akathisia risk may be necessary 1
• Quetiapine or olanzapine have lower akathisia rates than lurasidone, though metabolic monitoring intensifies 1

Monitoring Protocol

• Assess akathisia severity weekly using standardized scales (Barnes Akathisia Rating Scale) for the first month 3
• Monitor blood pressure and heart rate at each visit, particularly if any beta-blocker dose adjustments occur 1
• Evaluate for treatment-emergent sedation with mirtazapine, though the 7.5 mg dose minimizes this risk 2
• Reassess mood stability to ensure akathisia treatment does not destabilize bipolar disorder 5

Critical Pitfalls to Avoid

• Never combine two beta-blockers without cardiology consultation—the cardiovascular risks outweigh potential akathisia benefits 1
• Avoid anticholinergic agents (benztropine, trihexyphenidyl) for akathisia—they are ineffective and may worsen symptoms 1, 3
• Do not abruptly discontinue carvedilol if prescribed for cardiac indications—this can precipitate rebound hypertension or cardiac decompensation 1
• Recognize that akathisia increases suicide risk and treatment non-adherence in bipolar disorder—aggressive management is essential 3

If Propranolol Is Absolutely Necessary

Should clinical circumstances mandate propranolol despite these concerns:

• Discontinue carvedilol first with cardiology approval if it was prescribed for non-cardiac indications 1
• If carvedilol is medically necessary (heart failure, post-MI), propranolol is contraindicated—use mirtazapine instead 2
• Never titrate propranolol above 30 mg twice daily when any cardiovascular medication is present 6