ClinCalc Pro
Menu
Calculators Drugs Pathways AI Dx Donate Get the App
Centrally Acting Antihypertensive Pregnancy: Used in pregnancy — extensive safety record from the 1960s

Methyldopa (Chronic Hypertension in Pregnancy)

Brand names: Aldomet

Adult dose

Dose: 250 mg two to three times daily, increased as needed; maximum 3 g/day
Route: Oral
Frequency: Two to three times daily
Max: 3 g/day
First-line for chronic hypertension in pregnancy per NICE NG133. Onset 4–6h; not suitable for acute hypertensive emergencies. Discontinue at 2 days post-delivery (risk of postnatal depression with prolonged use).

Paediatric dose

Route: N/A
Frequency: N/A
Max: N/A
Not applicable in obstetric indication

Dose adjustments

Renal

Reduce dose in renal impairment — prolonged half-life

Hepatic

Avoid in active hepatic disease

Clinical pearls

  • NICE NG133 first-line oral antihypertensive for chronic hypertension in pregnancy — extensive safety data
  • Sedation is most troublesome early side effect — warn patients; often improves after 1–2 weeks
  • DISCONTINUE at 2 days post-delivery — associated with postnatal depression if continued postpartum
  • Positive Coombs test in ~20% (does not usually indicate haemolysis — clinical judgement required)
  • Long-standing safety record in pregnancy — follow-up studies of children born to methyldopa-treated mothers show no developmental concerns

Contraindications

  • Active liver disease or hepatitis
  • Phaeochromocytoma
  • Depression
  • MAOI therapy

Side effects

  • Drowsiness and sedation (common, especially initial days)
  • Dry mouth
  • Positive Coombs test (10–20%)
  • Haemolytic anaemia (rare)
  • Depression (postnatal risk if continued post-delivery)
  • Hepatotoxicity (rare)

Interactions

  • MAOIs — hypertensive crisis (contraindicated)
  • Lithium — increased lithium toxicity
  • Antidepressants — reduced antihypertensive efficacy

Monitoring

  • Blood pressure (routine monitoring)
  • LFTs (if symptomatic hepatic disease)
  • Coombs test (if anaemia develops)
  • Mood assessment postnatally if continued past delivery

Reference: BNFc; NICE NG133 Hypertension in Pregnancy; BNF; RCOG Chronic Hypertension Guidance. Verify against your local formulary and the latest BNF before prescribing.

Related

Curated clinical cross-links plus same-class fallbacks.

Calculators
Pathways