Hydralazine (By mouth)


Hydralazine Hydrochloride (hye-DRAL-a-zeen hye-droe-KLOR-ide)
Treats high blood pressure and heart failure. This medicine is a vasodilator.

Brand Name(s)

There may be other brand names for this medicine.


When This Medicine Should Not Be Used

You should not use this medicine if you have ever had an allergic reaction to hydralazine.

How to Use This Medicine

  • Your doctor will tell you how much to take and how often.
  • Take this medicine exactly as your doctor ordered. Even if you feel fine your blood pressure can still be high.
  • It is best to take your medicine on an empty stomach, 1 hour before or 2 hours after meals.
If a dose is missed:
  • Take the missed dose as soon as you remember.
  • Skip the missed dose if it is almost time for your next regular dose and return to your regular dosing schedule.
  • You should not use two doses at the same time.

How to Store and Dispose of This Medicine

  • Store at room temperature, away from heat, moisture, and direct light.
  • Keep all medicine out of the reach of children.

Drugs and Foods to Avoid

Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.
  • Make sure your doctor knows if you are taking diazoxide (Proglycem®), or MAO inhibitors such as Nardil®, Parnate®, or Marplan®.

Warnings While Using This Medicine

  • Check with your doctor before taking if you have heart or kidney disease, asthma, lupus or if you have had a stroke.
  • Talk with your doctor before use if you are pregnant or breastfeeding.
  • Hydralazine can make some people dizzy or drowsy, be careful if you drive a car or operate machinery.

Possible Side Effects While Using This Medicine

Call your doctor right away if you notice any of these side effects:
  • Chest pain
  • Trouble breathing
  • Skin rash, blisters, severe itching or hives
  • Fever, chills, or sore throat
  • Unusual bruising or bleeding
  • Joint pain
  • Swelling of the feet or legs
If you notice these less serious side effects, talk with your doctor:
  • Headache, dizziness, or lightheadedness
  • Fast heartbeat
  • Numbness or tingling in the hands or feet
  • Appetite loss, nausea, or vomiting
  • Diarrhea or constipation
  • Stuffy nose or watery eyes
  • Facial flushing (redness)

If you notice other side effects that you think are caused by this medicine, tell your doctor

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088
Review Date: 2011-02-04 Reviewed By: Keywords: ,
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