Hydralazine

1 medicine

Hydralazine is a direct-acting vasodilator used for high blood pressure and heart failure; with long-term use it can trigger a reversible lupus-like syndrome, so watch for new joint pain, rash, or fever.

Apresoline

Hydralazine

25mg

Apresoline is a heart blood pressure medication containing Hydralazine, available as 25mg tablets.

from $0.54 / tablet View

Key facts

  • Hydralazine (found in combination heart-failure treatments such as BiDil) is a direct-acting vasodilator. It relaxes the muscle in artery walls, easing the heart's workload and lowering blood pressure.
  • It's taken by mouth two to four times a day, or given by injection for a hypertensive emergency; the oral effect builds over the first few weeks.
  • Long-term use, especially at higher doses, can trigger a reversible lupus-like syndrome: joint pain, rash, and fever that clear once the drug is stopped.
  • Seek urgent care for chest pain, a rapid or pounding heartbeat, or severe joint swelling with fever.

What hydralazine treats

Hydralazine treats high blood pressure that has not responded well to other medicines, often alongside a diuretic and a beta-blocker to offset its side effects. Combined with isosorbide dinitrate, it treats heart failure, particularly in patients who cannot take an ACE inhibitor or ARB. Given by injection, it also brings down dangerously high blood pressure in hospital, including severe hypertension in pregnancy.

How hydralazine works

Hydralazine acts directly on the smooth muscle in arterial walls, causing it to relax. This widens the arteries and lowers the resistance the heart pumps against, so blood pressure falls and the heart's workload eases. Because it doesn't act through the nervous system, the drop in resistance often triggers a reflex increase in heart rate, which is why it's usually paired with a beta-blocker.

Before you take it

  • Avoid hydralazine if you have coronary artery disease or rheumatic heart disease affecting the mitral valve; reflex tachycardia can worsen angina.
  • Tell your prescriber about lupus or another autoimmune condition, kidney or liver disease, or a stroke, since these can change your dose.
  • Combining it with alcohol or other blood-pressure medicines can cause your blood pressure to fall too far.
  • Long courses at high doses raise lupus-syndrome risk; your prescriber may test your blood periodically.

Side effects

Common effects include headache, flushing, nausea, and a fast heartbeat, which often ease as your body adjusts.

Stop and seek urgent medical care for any of these:

  • New joint pain, swelling, rash, or unexplained fever.
  • Chest pain or a rapid, irregular heartbeat.
  • Numbness or tingling in the hands or feet.
  • Swelling of the face, lips, or throat.

Safety essentials

  • Drug-induced lupus is the defining long-term risk. Report new joint pain, rash, or fever promptly; symptoms usually resolve within weeks of stopping the drug.
  • Reflex tachycardia and fluid retention are common, which is why hydralazine is usually combined with a beta-blocker and a diuretic.
  • Take it at evenly spaced times each day, and don't stop a long-term regimen abruptly without medical advice.

This page is educational and does not replace advice from a doctor or pharmacist who knows your health history.