Mechanism of Action: Works by directly relaxing the muscles in the walls of the arteries, causing them to widen (dilate), thereby lowering blood pressure by allowing blood to flow more freely.
Indications
Primary Use: Treatment of hypertension (high blood pressure).
Other Uses: Often used in combination with other medications to treat severe hypertension and to manage heart failure.
Dosage
Adults: Initial dose typically starts at 10 mg four times daily. Based on response and tolerability, it may be gradually increased. Usual maintenance dose ranges from 25 to 50 mg four times daily.
Elderly: May require lower doses due to increased sensitivity to blood pressure changes.
Children: Dosage needs to be carefully adjusted based on weight and blood pressure response.
Administration
Method: Oral intake.
Precautions: Should be taken with meals to enhance absorption and reduce gastrointestinal side effects.
Forms Available
Tablets: 10 mg, 25 mg, 50 mg, 100 mg
Side Effects
Common: Headache, palpitations, flushing, nausea, and dizziness.
Less Common: Tachycardia (rapid heart rate), gastrointestinal disturbances, nasal congestion.
Rare but Serious: Lupus-like syndrome, peripheral neuropathy, hepatotoxicity, and severe hypotension.
Warnings
Black Box Warning: None.
Contraindications: Known hypersensitivity to hydralazine, coronary artery disease, mitral valvular rheumatic heart disease.
Precautions
General: Use cautiously in patients with cerebrovascular disease or those prone to hypotension.
Health Conditions: Regular monitoring is essential in patients with previous heart conditions, as hydralazine can cause fluid retention and exacerbate angina.
Interactions
Medications: The hypotensive effect can be enhanced by other antihypertensive agents. May increase levels of drugs metabolized by acetylation, such as procainamide.
Food: No significant food interactions, but taking it with food can reduce gastrointestinal side effects.
Monitoring Parameters
Blood Pressure: Regular monitoring, especially during initial treatment and dose adjustments.
Heart Rate: Monitor for signs of tachycardia.
Blood Tests: Regular liver function tests and complete blood count to monitor for potential adverse effects.
Use in Children
Guidelines: Effective and generally safe in pediatric patients when dosed appropriately; monitor closely for side effects.
Use in Pregnancy
FDA Category: C. Should only be used if the potential benefits justify the potential risks to the fetus. Has been used safely in pregnant women with severe hypertension.
Use in Elderly
Considerations: More likely to experience orthostatic hypotension. Doses should be adjusted cautiously.
Use in Kidney Disease
Adjustments: May require dose adjustments depending on the severity of renal impairment.
Use in Liver Disease
Caution: Use with caution as it can affect liver function; monitor liver enzymes regularly.
Patient Counselling Points
Medication Use: Importance of adherence to prescribed dosages and not missing doses to maintain effective control of blood pressure.
Side Effects: Awareness of potential side effects such as dizziness and to report symptoms like joint pain or any signs of heart problems.
Lifestyle: Encourage lifestyle changes that help manage blood pressure such as diet, exercise, and weight management.
Table of Brand Names, Manufacturer, and Prices in USD
Brand Name
Manufacturer
Strength/Dosage Form
Price (USD)
Apresoline
Novartis
50 mg Tablet
$0.50
15 FAQs with Answers
What is Hydralazine used for? – Primarily to lower high blood pressure.
How does Hydralazine work? – It relaxes blood vessels, lowering blood pressure and improving blood flow.
Can Hydralazine be taken with other blood pressure medications? – Yes, it’s often used in combination with other medications for better control.
What are the common side effects of taking Hydralazine? – Headache, nausea, and dizziness are common.
Is Hydralazine safe during pregnancy? – It’s classified as Category C but is used in pregnancy under close supervision.
Can children take Hydralazine? – Yes, under appropriate medical supervision.
How should Hydralazine be taken? – With meals to reduce stomach upset.
What should I do if I miss a dose? – Take it as soon as you remember unless it’s near the time of the next dose.
Does Hydralazine affect heart rate? – It can cause tachycardia; heart rate should be monitored.
Can Hydralazine cause lupus-like symptoms? – Yes, it can cause a lupus-like syndrome that is generally reversible.
Who should not take Hydralazine? – Those with coronary artery disease or severe valvular heart disease.
How often should my blood pressure be checked? – Regularly, as directed by your healthcare provider.
What lifestyle changes should accompany Hydralazine therapy? – Dietary adjustments, regular physical activity, and weight control.
Can I drink alcohol while taking Hydralazine? – Alcohol may increase certain side effects and should be used cautiously.
What monitoring is required with Hydralazine use? – Blood pressure, heart rate, liver function, and complete blood count should be monitored regularly.