What is BiDil, and how does it work?

BiDil (isosorbide dinitrate and hydralazine hcl) is a combination of a nitrate and a vasodilator used to treat heart failure.

What are the side effects of BiDil?

Common side effects of BiDil include:

Tell your doctor if you have unlikely but serious side effects of BiDil including:

What is the dosage for BiDil?

  • BiDil should be initiated at a dose of one BiDil Tablet, three times a day. Titrate to a maximum of two tablets three times daily, if tolerated.
  • Although titration of BiDil can be rapid (3-5 days), some patients may experience side effects and may take longer to reach their maximum tolerated dose.
  • The dosage may be decreased to as little as one-half BiDil Tablet three times a day if intolerable side effects occur.
  • Efforts should be made to titrate up as soon as side effects subside.

What drugs interact with BiDil?

Phosphodiesterase Inhibitors

  • BiDil is contraindicated in patients who are using a selective inhibitor of cyclic guanosine monophosphate (cGMP)- specific phosphodiesterase type 5 (PDE5), PDE5 inhibitors such as avanafil, sildenafil, vardenafil, and tadalafil have been shown to potentiate the hypotensive effects of organic nitrates.
  • Do not use BiDil in patients who are taking the soluble guanylate cyclase (sGC) stimulator riociguat. Concomitant use can cause hypotension.

Is BiDil safe to use while pregnant or breastfeeding?

  • There are no studies using BiDil in pregnant women.
  • A meta-analysis of randomized controlled trials comparing hydralazine hydrochloride with other antihypertensive agents for severe hypertension in pregnancy found that hydralazine hydrochloride was associated with significantly more
  • A combination of propranolol and hydralazine hydrochloride was administered to 13 patients with longstanding hypertension during 15 pregnancies.
  • These pregnancies resulted in 14 live births and one unexplained stillbirth.
  • The only neonatal complications were two cases of mild hypoglycemia.
  • Hydralazine hydrochloride and its metabolites have been detected using a non-selective assay in maternal and umbilical plasma in patients treated with the drug during pregnancy.
  • Isosorbide dinitrate has been used for effective acute and sub-chronic control of hypertension in pregnant women, but there are no studies using it in a chronic regimen and assessing its effects on pregnant women and/or the fetus.
  • No studies have been performed with BiDil.
  • It is not known if either hydralazine or isosorbide dinitrate is excreted in human milk.


In the U.S., 1 in every 4 deaths is caused by heart disease. See Answer


BiDil (isosorbide dinitrate and hydralazine hcl) is a combination of a nitrate and a vasodilator used to treat heart failure. Common side effects of BiDil include headache, dizziness, lightheadedness, weakness, nausea, vomiting, fast heartbeat, swollen ankles, and flushing (redness of the face, neck, and chest) as your body adjusts to the medication.

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Medically Reviewed on 12/11/2020
All sections courtesy of the U.S. Food and Drug Administration