Acute therapies for PRES
| Drug | Mechanism of action | Dose |
| First-line antihypertensive agents | ||
| Labetalol | Alpha-1 blocker/non-selective beta blocker | Initial: 20 mg slow injection over 3 min Titrate: additional 40 mg at 10 min intervals until achieving the desired BP reduction or until 300 mg has been injected |
| Nicardipine | Dihydropyridine calcium channel blocker | Initial: 5 mg/hour Titrate: Increase by 2.5 mg/hour every 5–15 min until achieving the desired BP reduction |
| Nimodipine | Calcium channel blocker | Initial: 0.5–1 mg/hour (15mcg/kg/hour) Titrate: increase to 2 mg/hour (30 mg/kg/hour) |
| Second-line antihypertensive agents | ||
| Enalapril | ACE inhibitor | Dose: 1.25 mg intravenously four times per day. Notes: Use for less than 48 hours, avoid in pregnancy |
| Hydralazine | Vasodilator by direct relaxation of vascular smooth muscle | Dose: 1.7–3.5 mg/kg divided into four to six doses |
| Sodium nitroprusside | Initial dose: 0.25–0.5 mcg/kg/min Titrate: increase by 0.2 mcg/kg/min until desired clinical response Maximum dose: 6 mcg/kg/min | |
| Antiseizure medications | ||
| Sodium valproate | Initial loading dose: 30–40 mg/kg (maximum dose of 3500 mg) Continuing dose: 400–1000 mg two times per day (maximum dose 2000 mg two times per day) | |
| Phenytoin | Initial loading dose: 15–20 mg/kg (maximum dose of 1500 mg) Continuing dose: 4–8 mg/kg initially titrating to plasma concentration of 15–20 mg/L Initial infusion rate cannot exceed 50 mg/min. | |
| Levetiracetam | Initial loading dose: 40–60 mg/kg (maximum dose 6000 mg) Continuing dose: 500–1000 mg two times per day (maximum dose 2000 mg two times per day) | |
BP, blood pressure; PRES, posterior reversible encephalopathy syndrome.