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Hydralazine

ATC code C02DB02

Also known as: Hydralazin, Hidralazin

Key facts
Active substance
Hydralazine
ATC code
C02DB02
Authorisation
authorised nationally; no central EU authorisation
Information as of
2026-10-29

Key facts

Hydralazine is a direct-acting peripheral vasodilator antihypertensive. Per the US prescribing information, the tablets are used to treat essential hypertension, alone or as an adjunct.

What it is used for

  • Essential hypertension, alone or as an adjunct to other therapy

Dosing

  • Start with 10 mg four times daily for the first 2 to 4 days, then 25 mg four times daily for the rest of the first week
  • From the second week: 50 mg four times daily; for maintenance, the lowest effective dose
  • In a few resistant patients up to 300 mg daily may be required; a lower dose combined with a thiazide, reserpine or a beta blocker may be considered
  • Toxic reactions, particularly the lupus-like (L.E. cell) syndrome, are more frequent with large doses
  • Taking it with food results in higher plasma levels

Contraindications

  • Hypersensitivity to hydralazine
  • Coronary artery disease
  • Mitral valvular rheumatic heart disease

Important warnings

  • A syndrome resembling systemic lupus erythematosus, including glomerulonephritis; discontinue unless continued therapy is required
  • Myocardial stimulation can cause angina attacks and ECG signs of ischemia; caution with suspected coronary artery disease
  • Caution in advanced renal damage and after cerebrovascular accidents; postural hypotension may occur
  • Peripheral neuritis; pyridoxine should be added if symptoms develop
  • Complete blood counts and antinuclear antibody titers before and periodically during prolonged therapy; blood dyscrasias have been reported

Side effects

  • Common: headache, anorexia, nausea, vomiting, diarrhea, palpitations, tachycardia, angina pectoris
  • Less frequent: hypotension, edema, dizziness, tremors, peripheral neuritis, nasal congestion, flushing
  • Blood dyscrasias, hypersensitivity reactions (rash, fever, arthralgia) and rarely hepatitis

Interactions

  • MAO inhibitors: use with caution
  • Potent parenteral antihypertensives such as diazoxide: profound hypotension may occur – observe continuously for several hours

Pregnancy and breastfeeding

  • No adequate and well-controlled studies in pregnant women; use only if the expected benefit justifies the potential risk to the fetus
  • Excreted in breast milk

Summary of the official product information, written with AI on 2026-10-29. Every number was checked automatically against the original text. Not reviewed by a physician – the full official text is authoritative.

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For patients

Patient information (US)

This product has no separate US patient information.

Authorisation and brand names by country

Medicines with exactly this active-substance composition, as listed in the national registers – alphabetical and without ranking. Whether a product is currently available is not shown here.

Brand names in 5 more European countries
Cyprus
Hydralazine Remedica
Malta
Hydralazine Remedica
Norway
Apresolin
Spain
Hydrapres
Sweden
Apresolin

EMA – Article 57 product data (EU/EEA), 2026-10-29

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Sources

  1. U.S. Food and Drug Administration. Hydralazine Hydrochloride (Heritage Pharmaceuticals Inc. d/b/a Avet Pharmaceuticals Inc.) – Prescribing Information, 2026-04-03. DailyMed (NLM), 2026-10-29. https://dailymed.nlm.nih.gov/dailymed/lookup.cfm?setid=669532c9-ba15-4f4b-95a8-13782deb3521

Editorial: Medelix editorial team · last updated 2026-10-29 · How these pages are made · Report an error

Source: U.S. Food and Drug Administration (FDA), prescribing information, via DailyMed (NLM); public domain. Not advertising, not a treatment recommendation. For questions about your own treatment, ask your doctor or pharmacist.