Hydralazine Uses, Dosage, Side Effects, Food Interaction and all others data.
Originally developed in the 1950s as a malaria treatment, hydralazine showed antihypertensive ability and was soon repurposed. Hydralazine is a hydrazine derivative vasodilator used alone or as adjunct therapy in the treatment of hypertension and only as adjunct therapy in the treatment of heart failure. Hydralazine is no longer a first line therapy for these indications since the development of newer antihypertensive medications.
Hydralazine hydrochloride was FDA approved on 15 January 1953.
Hydralazine interferes with calcium transport to relax arteriolar smooth muscle and lower blood pressure. Hydralazine has a short duration of action of 2-6h. This drug has a wide therapeutic window, as patients can tolerate doses of up to 300mg. Patients should be cautioned regarding the risk of developing systemic lupus erythematosus syndrome.
|Hydralazine Other Names
|1-Hydrazinophthalazine, 1-Phthalazinylhydrazine, 6-Hydralazine, Hidralazina, Hydralazin, Hydralazine, Hydralazinum, Hydrallazine, Hydrazinophthalazine, Hypophthalin, Idralazina
|amlodipine, lisinopril, metoprolol, losartan, furosemide, carvedilol, hydrochlorothiazide, spironolactone, nifedipine, captopril
|25mg, 20mg, , 10mg, 100mg, 50mg, 20mg/ml
|Tablet, Injection, Infusion, Oral Tablet, Oral
Hydralazine is 87% protein bound in serum likely to human serum albumin.
|Zafa Pharmaceutical Laboratories (pvt) Ltd, , Advanz Pharma, Ciron Drugs & Pharma Pvt Ltd, Alpa Laboratories Pvt Ltd
|Pakistan, United Kingdom, United States, India, Nigeria
|September 19, 2023 at 7:00 am
Hydralazine is an antihypertensive agent used for the management of essential hypertension or severe hypertension associated with conditions requiring immediate action, heart failure, and pre-eclampsia or eclampsia .
Hydralazine is indicated alone or adjunct to standard therapy to treat essential hypertension. A combination product with isosorbide dinitrate is indicated as an adjunct therapy in the treatment of heart failure.
How Hydralazine works
Hydralazine may interfere with calcium transport in vascular smooth muscle by an unknown mechanism to relax arteriolar smooth muscle and lower blood pressure. The interference with calcium transport may be by preventing influx of calcium into cells, preventing calcium release from intracellular compartments, directly acting on actin and myosin, or a combination of these actions. This decrease in vascular resistance leads to increased heart rate, stroke volume, and cardiac output.
Hydralazine also competes with protocollagen prolyl hydroxylase (CPH) for free iron. This competition inhibits CPH mediated hydroxylation of HIF-1α, preventing the degradation of HIF-1α. Induction of HIF-1α and VEGF promote proliferation of endothelial cells and angiogenesis.
The oral LD50 in rats is 173-187mg/kg and the highest known dose an adult human has survived is 10g orally.
Patients experiencing an overdose may present with hypotension, tachycardia, headache, flushing, myocardial ischemia, myocardial infarction, cardiac arrhythmia, and shock. Overdose can be treated through emptying the gastric contents and administering activated charcoal, though these treatments may cause further arrhythmias and shock. Supportive and symptomatic treatment should be administered.
- Take with or without food. Food increases exposure to hydralazine, though this may not be clinically significant.
Hydralazine Drug Interaction
Moderate: aspirin, aspirinMinor: furosemide, furosemide, metoprolol, metoprolol, metoprolol, metoprololUnknown: apixaban, apixaban, omega-3 polyunsaturated fatty acids, omega-3 polyunsaturated fatty acids, insulin glargine, insulin glargine, clopidogrel, clopidogrel, cyanocobalamin, cyanocobalamin, cholecalciferol, cholecalciferol
Hydralazine Disease Interaction
Volume of Distribution
The volume of distribution is 1.34±0.79L/kg in congestive heart failure patients and 1.98±0.22L/kg in hypertensive patients.
Taking oral hydralazine with food improves the bioavailability of the drug. An intravenous dose of 0.3mg/kg leads to an AUC of 17.5-29.4µM*min and a 1mg/kg oral dose leads to an AUC of 4.0-30.4µM*min. The Cmax of oral hydralazine is 0.12-1.31µM depending on the acetylator status of patients.
Hydralazine has a half life of 2.2-7.8h in rapid acetylators and 2.0-5.8h in slow acetylators. The half life in heart failure patients is 57-241 minutes with an average of 105 minutes and in hypertensive patients is 200 minutes for rapid acetylators and 297 minutes for slow acetylators.
The majority of hydralazine clearance is extrahepatic- 55% for rapid acetylators and 70% for slow acetylators. The average clearance in congestive heart failure patients is 1.77±0.48L/kg/h, while hypertensive patients have an average clearance of 42.7±8.9mL/min/kg.
You find simplified version here Hydralazine