Table 2. Drugs for Gestational or Chronic Hypertension in Pregnancy

Drug (FDA Risk)*DoseConcerns or Comments
No antihypertensive has been proven safe for use during the first trimester. Drug therapy was indicated for uncomplicated chronic hypertension when diastolic BP was ≥100 mm Hg (Korotkoff V). Treatment at lower levels may be indicated for patients with diabetes mellitus, renal disease, or target organ damage. NHBPEP indicates National High Blood Pressure Education Program Working Group Report on High Blood Pressure in Pregnancy.
*Food and Drug Administration classification.
†We omit some agents (eg, clonidine and α-blockers) because of limited data on the use for chronic hypertension in pregnancy.
‡We would classify this in category X.
Preferred agent
Methyldopa (B)0.5 to 3.0 g/d in 2 divided dosesDrug of choice according to NHBEP; safety after first trimester well documented, including 7 years follow-up of offspring
Second-line agents
    Labetalol (C)200 to 1200 mg/d in 2 to 3 divided dosesMay be associated with fetal growth restriction
    Nifedipine (C)30 to 120 mg/d of a slow-release preparationMay inhibit labor and have synergistic action with magnesium sulfate in BP lowering; little experience with other calcium entry blockers
    Hydralazine (C)50 to 300 mg/d in 2 to 4 divided dosesFew controlled trials, long experience with few adverse events documented; useful in combination with sympatholytic agent; may cause neonatal thrombocytopenia
    β-Receptor blockers (C)Depends on specific agentMay decrease uteroplacental blood flow; may impair fetal response to hypoxic stress; risk of growth restriction when started in first or second trimester (atenolol); may be associated with neonatal hypoglycemia at higher doses
    Hydrochlorothiazide (C)12.5 to 25.0 mg/dMajority of controlled studies in normotensive pregnant women rather than hypertensive patients; can cause volume contraction and electrolyte disorders; may be useful in combination with methyldopa and vasodilator to mitigate compensatory fluid retention
    Contraindicated ACE-Is and angiotensin type 1 receptor antagonists (D)Leads to fetal loss in animals; human use associated with cardiac defects, fetopathy, oligohydramnios, growth restriction, renal agenesis and neonatal anuric renal failure, which may be fatal