Oral calcium-channel blockers are symptomatic: nimodipine 30–60 mg PO q4h (start lower if hypotensive; CYP3A4 interactions), verapamil SR 120–240 mg/day PO (headache relief commonly reported), with selective IV/IA verapamil rescue; taper over ~2–4 weeks as symptoms/velocities improve; prevention of stroke remains unproven (Mitsutake et al., 2025; Sreedharan et al., 2025; Madapoosi et al., 2025). This evidence concerns the gene CYP3A4 and Stroke.