Table 5.

Most commonly used drugs for treatment of hypertensive emergencies in pregnancy.

Adapted from Ref. [55]

Drug	Route	Onset of action	Duration of action	Starting dose	Titration dose	Maximum dose	Perinatal concerns	Contra-indications	Adverse effects
Labetalol	iv (intermittent)	5–10 min	2–6 h	10–20 mg iv (over 2 min)	20–80 mg iv every 20–30 min	300 mg	Foetal distress secondary to abrupt maternal hypotension; neonatal bradycardia and hypoglycaemia	II or III degree AV block; systolic heart failure; asthma; bradycardia	Bronchoconstriction (CAUTION in women with asthma); foetal bradycardia; postural hypotension; sleep disturbances; rebound hypertension; masking hypoglycaemia
	iv (infusion)			1-2 mg/min	Increase by 1 mg/min every 10 min
Hydralazine	iv (intermittent)	10 min	12 h	5 mg/ iv or im	5–10 mg iv every 20–40 min	30 mg	Foetal distress secondary to abrupt maternal hypotension; caesarian section; abruption; APGAR score < 7 more common; rarely neonatal thrombocytopenia and neonatal lupus		Headache; palpitations; tachycardia; nausea/vomiting; flushing; hypotension; lupus-like syndrome; CAUTION: side effects may mimic worsening pre-eclampsia
Nifedipine short acting formulation	Oral	5–10 min	2–4 h	10–20 mg	Repeat in 30 min if needed	30 mg	Foetal distress secondary to abrupt maternal hypotension; increased liver clearance may require higher doses		Uncontrolled hypotension (high when combined with magnesium sulphate); stroke; M (particularly when given sublingually); headache; flushing; reflex tachycardia
Nitroglycerine	iv (infusion)	1-5 min	3–5 min	5 µg/min	Increase by 5 µg/min every 5 min	200 µg/min			Headache; reflex tachycardia
Esmolol	iv (infusion)	< 1 min	15–30 min	Bolus 500 µg/kg; maintenance 50 µg/kg/min	Increase by 50 µg/kg/min every 4 min	300 µg/kg/min	Foetal bradycardia; resistant foetal beta-blockade	II or III degree AV block; systolic heart failure; asthma; bradycardia	First-degree heart block; maternal bradycardia; CHF; bronchospasm
Nicardipine	iv (infusion)	1-5 min	4–6 h	5 mg/h	Increase by 2.5 mg/h every 5-15 min	15 mg/h		liver failure	Tachycardia; flushing; headache
Urapidil	iv (infusion)	3-5 min	4–6 h	Bolus 12.5-25 mg; maintenance 5-40 mg/h		40 mg/h
Sodium nitroprusside	iv (infusion)	< 1 min	2–3 min	0.25 µg/kg/min	Increase by 0.25-0.5 µg/kg/min every 2-3 min	5 µg/kg/min	Foetal cyanide and thiocyanide toxicity if used > 4 h		Nausea; vomiting

AV atrioventricular, CHF chronic heart failure, iv intravenous, im intramuscular, NO nitric oxide