HYDRALAZINE
Background and Date of Approval
Hydralazine is a medication that belongs to the class of drugs known as vasodilators.
Uses
Hydralazine dissolves blood clots and restores blood flow in conditions such as acute ischemic stroke, acute myocardial infarction (heart attack), and pulmonary embolism.
How is it administered?
Hydralazine is used as a tablet. Swallow with a whole glass of water. Your healthcare professional will determine the specific dosage and administration guidelines based on your condition and needs.
Side Effects
Common side effects of hydralazine include headache, dizziness, flushing (reddening of the skin), rapid heartbeat, and nausea. More serious side effects may include lupus-like symptoms such as joint pain and skin rashes, severe chest pain, a significant drop in blood pressure leading to lightheadedness, and potential allergic reactions marked by swelling of the face, lips, or throat.
Warnings
Hydralazine can cause a significant drop in blood pressure, which may lead to symptoms like dizziness, lightheadedness, and fainting. It has been associated with a lupus-like syndrome, which can cause joint pain, fever, skin rashes, and other autoimmune-like symptoms. This medication can sometimes cause fluid retention, leading to swelling in the legs, ankles, or feet. It can have effects on the heart, including increasing the heart rate and potentially causing arrhythmias (irregular heartbeats). Rarely, hydralazine has been linked to peripheral neuropathy, a condition affecting the nerves outside the brain and spinal cord. This medication might worsen certain types of glaucoma due to its potential to increase intraocular pressure
Precautions
Exercise caution with hydralazine due to potential blood pressure drops causing dizziness, monitor lupus-like symptoms, consult for heart/liver/kidney conditions, limit alcohol intake, seek medical advice if pregnant/breastfeeding, avoid tasks needing alertness if experiencing drowsiness, and maintain open communication with a healthcare provider.
Word of Advice
Hydralazine can lower blood pressure significantly, which may cause dizziness and fainting. Rise slowly from sitting or lying positions to minimise sudden drops in blood pressure. Avoid alcohol while taking hydralazine, as it may intensify side effects. Patients with autoimmune disorders should monitor for lupus-like symptoms during treatment. Those with heart, liver, or kidney disease require healthcare provider consultation for appropriate monitoring and possible dose adjustments. Hydralazine may affect blood glucose levels in patients with diabetes and requires careful monitoring. Pregnant patients, those who are breastfeeding, or those planning pregnancy should consult their healthcare provider before use. Drowsiness, dizziness, and impaired coordination may occur; avoid driving or operating machinery requiring full alertness. Monitor your body's response to the medication and report any concerns to your healthcare provider promptly.
References
KD Tripathi, Essentials of Medical Pharmacology, Antihypertensive drugs, 7th edition, 2013, 566. Amdipharm UK Limited, Electronic medicines compendium (emc), [Revised on July 2019] [ Accessed on 21st March 2022], https://www.medicines.org.uk/emc/files/pil.6707.pdf
Frequently Asked Questions
What should I do if I miss a dose of hydralazine?
If you miss a dose, take it as soon as you remember. However, if it's close to the time for your next dose, skip the missed dose and resume your regular schedule.
Can hydralazine be used in children?
Hydralazine is typically not used in children except in specific cases and under medical supervision. Pediatric dosages and use should be discussed with a healthcare provider.
How long does it take for hydralazine to start working?
The onset of action can vary, but you might notice some effects within hours to a few days of starting hydralazine. However, it may take several weeks to reach its full effectiveness.
Can hydralazine interact with other medications?
Yes, hydralazine can interact with other medications, including antihypertensive drugs and drugs that affect blood pressure. Inform your healthcare provider about all medications you're taking.
Can hydralazine be taken during pregnancy?
Hydralazine's use during pregnancy should be discussed with a healthcare provider. The potential benefits and risks to the mother and the fetus will be considered.
What should I do if I experience side effects from hydralazine?
Contact your healthcare provider if you experience any side effects, especially severe or concerning ones. They can advise you on managing them or adjusting your treatment plan.
Can hydralazine be stopped abruptly?
It's generally not recommended to stop hydralazine abruptly. Your healthcare provider will guide you on discontinuing the medication safely if needed.