58 若王太太在使用首選用藥兩劑後，仍無法有效降低其血壓，可改用下列何項藥品？
(A) Metolazone
(B) Amlodipine
(C) Labetalol
(D) Valsartan

上一題的Hydralazine怎麼用：

Hypertensive emergency in pregnancy or postpartum (including acute-onset hypertension in preeclampsia/eclampsia) (off-label use): Note: For acute-onset, severe, persistent (eg, ≥15 minutes) hypertension (ACOG 2017).

IM, IV: Initial: 5 or 10 mg; repeat with 5 to 10 mg doses every 20 minutes if blood pressure continues to exceed thresholds (ACOG 2017; Magee 2014; Too 2013). If systolic blood pressure or diastolic blood pressure remains above threshold after a total cumulative dose of 20 to 30 mg, another agent should be used (ACOG 2017; August 2019).

仍無法有效降血壓可考慮本題的Labetalol

Labetalol怎麼用：

Hypertensive emergency in pregnancy (systolic BP ≥160 mm Hg or diastolic BP ≥110 mm Hg) (off-label dose):IV: Initial: 20 mg; if blood pressure still exceeds thresholds, may increase dose every 10 minutes in increments of 20 to 40 mg to a maximum single dose of 80 mg (Refer to administration protocols developed by the American College of Obstetricians and Gynecologists; ACOG 2015).

A maximum total cumulative dose of 300 mg is recommended (Magee 2014). Note: After the initial dose, may initiate a continuous infusion of 1 to 2 mg/minute instead of intermittent dosing (Magee 2014).

From Uptodate