Hydralazine: What is it? How is it used? Side Effects, Precautions, Overdose and Storage

Its function is to relax the blood vessels so that blood can flow through the body without complications.

It is a medication used to lower high blood pressure, helping to prevent strokes, heart attacks, and kidney problems.

How is Hydralazine used?

The treatment must be prescribed by a medical specialist to guarantee the drug’s effectiveness. However, it is usual to take it orally 2 to 4 times a day with or without food.

The dosage is subject to the degree of affection that the patient presents and how the body responds to treatment. In general, the dose always starts low and is gradually increased by medical tests and the advances or deteriorations that the disease may present.

The medication should be used regularly and recommended by the treating physician to ensure its effectiveness.

People who suffer from high blood pressure do not always have negative symptoms, so stop taking Hydralazine if notifying the treating doctor is a serious error, even if there are no significant complications.

Suppose the medicine generates adverse side effects for the health. In that case, the affected one must stop taking it progressively, always notifying the specialist so that it takes preventive measures and can treat the suffering with another drug.


Some conditions can get worse when Hydralazine stops suddenly.

Changes in lifestyle, such as exercise, healthy eating habits, and stress management, can help make this medicine work better.

Laboratory tests should be performed periodically, such as a complete blood count to monitor progress or detect degenerative health effects.

Blood pressure should be checked regularly while taking Hydralazine; it is usually positive to learn to control blood pressure to share with the treating doctor.

Side effects

  • Headache.
  • Sporadic arrhythmia .
  • Sickness.
  • Loss of appetite
  • Diarrhea.
  • Dizziness until the body adapts to the dosage of the medication.

In rare cases, this medication can cause nerve problems.

Other less frequent side effects are:

  • Inflammation in the joints.
  • Intense tiredness
  • Inflammation in the glands.
  • Acne.
  • Renal problems.
  • Sudden bruising
  • Bleeding

Allergic reactions are expected while the body adapts to the medication. Still, if they aggravate or threaten the patient’s physical and emotional stability, it is recommended to call the attending physician immediately.

The allergic symptoms are usually:

  • Itching in the body
  • Rash.
  • Inflammation of some parts, such as the tongue or throat.
  • Difficulty breathing.
  • Progressive dizziness and loss of the notion of time and space.


Hydralazine should not be used if there are some medical conditions such as heart disease or rheumatism in the heart’s mitral valve.

This medicine can threaten the life of the unborn, so it should only be taken in strictly critical situations during the gestation period.

If the patient is in the period of lactation, a treatment with Hydralazine is not recommended either because its components can pass into the milk, which would affect the baby.

This medicine mustn’t be shared with other people and less if they do not suffer from blood pressure, as it can cause irreversible adverse health effects.


Like any drug, its excessive use can lead to an overdose, which could hurt the organism, even until the death of the affected person.

It is counterproductive for people to be medically treated when they are treated with Hydralazine. Because it is a specific medicine to lower blood pressure, its excessive use is harmful to health.

It is usual to communicate with the treating doctor if it is believed that the drug is not working and a more potent dose is required because what may be necessary is to combine it with another medication to achieve better effects.


This medicine should be stored at an ambient temperature between 59 to 86 degrees Fahrenheit, always away from sunlight or moisture. It is not necessary to refrigerate and should be out of the reach of children or pets.

Suppose the Hydralazine is expired before throwing. It is recommended to call a pharmacist or the attending physician to validate if it can be ingested until a particular time or if its use should be ruled out immediately.