Evidence Summary
Evidence Level: Moderate
Mechanism: Enrollment: Actual, Enrollment: Estimated, Neurological / Autonomic, Sponsor Type: Fed
Safety: Bradycardia, visual phosphenes (luminous phenomena), headache. Contraindicated in sick sinus, severe hypotension, acute decompensated HF. Monitor HR.
Dosing: 2.5–7.5 mg twice daily; titrate to HR; durations in POTS/autonomic studies 4–12 weeks or longer.
Observational success ~55% + nested COVIVA RCT. Selective HR reduction without beta effects. 2.5-7.5mg BID. Visual side effects possible. Strong for hyperadrenergic POTS/IST phenotypes.