Labetalol = 1st line.
Labetalol 100-400 mg BID. Start 100 mg PO BID. May increase by 100 mg BID q2-3 days. Max dose: 2400 mg /day.
Methyldopa 250 -500 mg PO BID. Start 250 mg PO BID, then adjust q2 days. Max 3000 mg /day.
Nifedipine extended-release 30 to 90 mg daily. Start 30 to 60 mg daily and increase q1-2wks. Max 120 mg /day.
-Don’t use immediate release nifedipine (oral or sublingual) because it can cause a significant rapid decrease in BP.
Hydralazine 10-50 mg PO qid. Start 10 mg PO qid for 2-4 days, then increase by 25 mg PO qid x 1 week. Max 200 mg /day.
-Because of reflex tachycardia, don’t use oral hydralazine as monotherapy. You can use hydralazine as an add-on drug to methyldopa or labetalol.
-Don’t use hydralazine doses above 100 mg daily long-term because they are associated with an increased risk for developing lupus erythematosus, especially in women and slow acetylators. If you must, it’s recommended to check the acetylation status before increasing doses above 100 mg daily.
Contraindicated/not recommended
ACE-I and ARBS – because of the risk of birth defects and fetal or neonatal renal failure.
Metoprolol (a cardioselective BB) – is associated with fetal growth restriction. Avoid use in pregnancy.
Nifedipine immediate release is not recommended due to the risk of hypotension.