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Hydralazine Injection

Generic Name: hydralazine (hye-DRAL-a-zeen)
Brand Name: Generic only. No brands available.

Hydralazine injection is used for:

Treating severe high blood pressure in patients who cannot take hydralazine by mouth or when the need to lower blood pressure is urgent. It may also be used for other conditions as determined by your doctor.

Hydralazine is a vasodilator. It works by relaxing and dilating (opening) the blood vessels in the body, allowing blood to flow through the vessels more easily and at a lower pressure.

Do NOT use hydralazine injection if:

  • you are allergic to nitrates or to any ingredient in hydralazine injection
  • you have problems with the blood vessels of your heart (coronary artery disease) or certain heart valve problems (mitral valvular rheumatic heart disease)

Contact your doctor or health care provider right away if any of these apply to you.

Before using hydralazine injection:

Some medical conditions may interact with hydralazine injection. Tell your doctor or pharmacist if you have any medical conditions, especially if any of the following apply to you:

  • if you are pregnant, planning to become pregnant, or are breast-feeding
  • if you are taking any prescription or nonprescription medicine, herbal preparation, or dietary supplement
  • if you have allergies to medicines, foods, or other substances
  • if you have blood problems (eg, porphyria), blood vessel problems, heart problems, low blood pressure, low levels of vitamin B6 in your blood, kidney problems, or lupus
  • if you have a history of stroke

Some MEDICINES MAY INTERACT with hydralazine injection. Tell your health care provider if you are taking any other medicines, especially any of the following:

  • Medicines that may affect your blood vessels, medicines that treat high blood pressure (eg, diazoxide), or other vasodilators (eg, isosorbide, nitroglycerin) because they may increase the risk of hydralazine's side effects. Check with your doctor or pharmacist if you have questions about which medicines may affect your blood vessels.
  • Monoamine oxidase (MAO) inhibitors (eg, phenelzine) because the risk of serious side effects may be increased
  • Beta-blockers (eg, propranolol) because the risk of their side effects may be increased by hydralazine injection
  • Epinephrine because its effectiveness may be decreased by hydralazine injection

This may not be a complete list of all interactions that may occur. Ask your health care provider if hydralazine may interact with other medicines that you take. Check with your health care provider before you start, stop, or change the dose of any medicine.

How to use hydralazine injection:

Use hydralazine injection as directed by your doctor. Check the label on the medicine for exact dosing instructions.

  • Hydralazine injection is usually given as an injection at your doctor's office, hospital, or clinic. If you will be using hydralazine injection at home, a health care provider will teach you how to use it. Be sure you understand how to use hydralazine injection. Follow the procedures you are taught when you use a dose. Contact your health care provider if you have any questions.
  • Do not use hydralazine injection if it contains particles, is cloudy or discolored, or if the vial is cracked or damaged.
  • Keep this product, as well as syringes and needles, out of the reach of children and pets. Do not reuse needles, syringes, or other materials. Ask your health care provider how to dispose of these materials after use. Follow all local rules for disposal.
  • If you miss a dose of hydralazine injection, take it as soon as possible. If it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not take 2 doses at once.

Ask your health care provider any questions you may have about how to use hydralazine injection.

Important safety information:

  • Hydralazine injection may cause dizziness. This effect may be worse if you take it with alcohol or certain medicines. Use hydralazine injection with caution. Do not drive or perform other possibly unsafe tasks until you know how you react to it.
  • Hydralazine injection may cause dizziness, lightheadedness, or fainting; alcohol, hot weather, exercise, or fever may increase these effects. To prevent them, sit up or stand slowly, especially in the morning. Sit or lie down at the first sign of any of these effects.
  • Tell your doctor or dentist that you take hydralazine injection before you receive any medical or dental care, emergency care, or surgery.
  • Lab tests, including complete blood counts, blood pressure, and antinuclear antibody titers, may be performed while you use hydralazine injection. These tests may be used to monitor your condition or check for side effects. Be sure to keep all doctor and lab appointments.
  • Hydralazine injection should be used with extreme caution in CHILDREN; safety and effectiveness in children have not been confirmed.
  • PREGNANCY and BREAST-FEEDING: If you become pregnant while taking hydralazine injection, contact your doctor. You will need to discuss the benefits and risks of using hydralazine injection while pregnant. It is not known if this medicine is found in breast milk. If you are or will be breast-feeding while you are using hydralazine injection, check with your doctor. Discuss any possible risks to your baby.

Possible side effects of hydralazine injection:

All medicines may cause side effects, but many people have no, or minor, side effects. Check with your doctor if any of these most COMMON side effects persist or become bothersome:

Diarrhea; headache; loss of appetite; nausea; vomiting.

Seek medical attention right away if any of these SEVERE side effects occur:

Severe allergic reactions (rash; hives; itching; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue); chest pain; decreased or difficult urination; depression; fainting; fast or irregular heartbeat; fever, chills, or sore throat; joint pain; mental or mood changes; numbness of an arm or leg; numbness or tingling of the skin; persistent fatigue or weakness; severe or persistent headache or dizziness; unusual bruising or bleeding; vision changes; yellowing of the eyes or skin.

This is not a complete list of all side effects that may occur. If you have questions about side effects, contact your health care provider. Call your doctor for medical advice about side effects. To report side effects to the appropriate agency, please read the Guide to Reporting Problems to FDA.

If OVERDOSE is suspected:

Contact 1-800-222-1222 (the American Association of Poison Control Centers), your local poison control center, or emergency room immediately. Symptoms may include chest pain; fast or irregular heartbeat; flushing; severe headache; shock.

Proper storage of hydralazine injection:

Hydralazine injection is usually handled and stored by a health care provider. If you are using hydralazine injection at home, store hydralazine injection as directed by your pharmacist or health care provider. Keep hydralazine injection out of the reach of children and away from pets.

General information:

  • If you have any questions about hydralazine injection, please talk with your doctor, pharmacist, or other health care provider.
  • Hydralazine injection is to be used only by the patient for whom it is prescribed. Do not share it with other people.
  • If your symptoms do not improve or if they become worse, check with your doctor.
  • Check with your pharmacist about how to dispose of unused medicine.

This information should not be used to decide whether or not to take hydralazine injection or any other medicine. Only your health care provider has the knowledge and training to decide which medicines are right for you. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about hydralazine injection. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to hydralazine injection. This information is not specific medical advice and does not replace information you receive from your health care provider. You must talk with your healthcare provider for complete information about the risks and benefits of using hydralazine injection.

Review Date: April 11, 2017

Disclaimer: This information should not be used to decide whether or not to take this medicine or any other medicine. Only your health care provider has the knowledge and training to decide which medicines are right for you. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about this medicine. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to this medicine. This information is not specific medical advice and does not replace information you receive from your health care provider. You must talk with your healthcare provider for complete information about the risks and benefits of using this medicine.

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