Methyldopa

Products

Methyldopa is commercially available in the form of film-coated tablets (Aldomet). It has been approved in many countries since 1962.

Structure and properties

Methyldopa (C10H13NO4, Mr = 211.2 g/mol) is an α-methylated derivative of the amino acid and dopamine precursor levodopa. It is present in drugs as anhydrous methyldopa (Methyldopum anhydricum) or as methyldopa sesquihydrate (1.5 H2O), a white to yellowish white crystalline powder or colorless to nearly colorless crystals, which are sparingly soluble in water. Methyldopa is a prodrug. The metabolite α-methylnorepinephrine is responsible for the effects.

Effects

Methyldopa (ATC C02AB01) has antihypertensive properties. The effects are due to central stimulation of adrenergic α2-receptors and a decrease in sympathetic tone. We cannot make a definitive statement regarding safety during pregnancy because we did not systematically assess the available studies. In the scientific literature, methyldopa is largely considered safe and not harmful to fertility and is among the 1st-choice agents for longer-term treatment of hypertension during pregnancy.

Indications

For the treatment of high blood pressure (hypertension). Methyldopa is mainly used for the treatment of gestational hypertension.

Dosage

According to the SmPC. For the treatment of gestational hypertension, comparatively high daily doses of 1000 mg to a maximum of 2000 mg may be administered throughout the day. Methyldopa should not be administered concomitantly with iron supplements because they reduce the bioavailability of the drug. Concurrent alcohol consumption should be avoided because an intolerance reaction may result.

Contraindications

  • Hypersensitivity
  • Acute or chronic liver disease
  • Severe renal dysfunction
  • Severe heart failure
  • Coombs-positive hemolytic anemia
  • Pheochromocytoma
  • Treatment with an MAO inhibitor

For complete precautions, see the drug label.

Interactions

Drug interactions are possible with antihypertensives, beta-blockers, lithium, anesthetics, iron supplements, MAO inhibitors, and alcohol, among others.

Adverse effects

The most common possible adverse effects include drowsiness, dizziness, headache, dizziness, dullness, sleep disturbances, depressed mood, hallucinations, circulatory problems, digestive problems, darkening of the urine, and edema. Methyldopa is hepatotoxic. Liver dysfunction, jaundice, and hepatitis rarely occur. Other side effects are possible. In the newborn, tremors and irritability may be observed after birth if the mother has been treated.