Table 2

Acute therapies for PRES

DrugMechanism of actionDose
First-line antihypertensive agents
LabetalolAlpha-1 blocker/non-selective beta blockerInitial: 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
NicardipineDihydropyridine calcium channel blockerInitial: 5 mg/hour
Titrate: Increase by 2.5 mg/hour every 5–15 min until achieving the desired BP reduction
NimodipineCalcium channel blockerInitial: 0.5–1 mg/hour (15mcg/kg/hour)
Titrate: increase to 2 mg/hour (30 mg/kg/hour)
Second-line antihypertensive agents
EnalaprilACE inhibitorDose: 1.25 mg intravenously four times per day.
Notes: Use for less than 48 hours, avoid in pregnancy
HydralazineVasodilator by direct relaxation of vascular smooth muscleDose: 1.7–3.5 mg/kg divided into four to six doses
Sodium nitroprussideInitial 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 valproateInitial 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)
PhenytoinInitial 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.
LevetiracetamInitial 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.