Hydralazine Tablets 25Mg (1 Strip = 10 Tablets)

Requires Prescription (YES/NO)

Yes

Generics

Hydralazine HCl

Used For

Hypertension

How it works

Although the precise mechanism of action of hydralazine is not fully understood, the major effects are on the cardiovascular system. Hydralazine apparently lowers blood pressure by exerting a peripheral vasodilating effect through a direct relaxation of vascular smooth muscle. Hydralazine, by altering cellular calcium metabolism, interferes with the calcium movements within the vascular smooth muscle that are responsible for initiating or maintaining the contractile state. The peripheral vasodilating effect of hydralazine results in decreased arterial blood pressure (diastolic more than systolic); decreased peripheral vascular resistance; and an increased heart rate, stroke volume, and cardiac output. The preferential dilatation of arterioles, as compared to veins, minimizes postural hypotension and promotes the increase in cardiac output. Hydralazine usually increases renin activity in plasma, presumably as a result of increased secretion of renin by the renal juxtaglomerular cells in response to reflex sympathetic discharge. This increase in renin activity leads to the production of angiotensin II, which then causes stimulation of aldosterone and consequent sodium reabsorption. Hydralazine also maintains or increases renal and cerebral blood flow.

Dosage

Hydralazine HCl

Side Effects

Common: Headache, anorexia, nausea, vomiting, diarrhea, palpitations, tachycardia, angina pectoris. Less Frequent: Digestive: constipation, paralytic ileus. Cardiovascular: hypotension, paradoxical pressor response, edema. Respiratory: dyspnea. Neurologic: peripheral neuritis, evidenced by paresthesia, numbness, and tingling; dizziness; tremors; muscle cramps; psychotic reactions characterized by depression, disorientation, or anxiety. Genitourinary: difficulty in urination. Hematologic: blood dyscrasias, consisting of reduction in hemoglobin and red cell count, leukopenia, agranulocytosis, purpura; lymphadenopathy; splenomegaly. Hypersensitive Reactions: rash, urticaria, pruritus, fever, chills, arthralgia, eosinophilia, and, rarely, hepatitis. Other: nasal congestion, flushing, lacrimation, conjunctivitis.

Drug Interactions

MAO inhibitors , antihypertensive drugs, such as diazoxide .

Indication

Hydralazine used to: • Treat moderate to severe high blood pressure (with or without a betablocker or diuretic medicine) • Manage moderate to severe congestive heart failure (where use of other medicines alone is not enough).

When not to Use

Do not take Hydralazine if you have: • An allergy to hydralazine, dihydralazine or any of the other ingredients in this medicine. • A racing heartbeat (tachycardia) • Heart failure caused by narrowing of blood vessels or heart valves (aortic or mitral stenosis), high blood pressure in blood vessels supplying the lungs (pulmonary hypertension) or inflammation of the heart (constrictive pericarditis) .

Precaution

Myocardial stimulation produced by hydralazine can cause anginal attacks and ECG changes of myocardial ischemia. The drug has been implicated in the production of myocardial infarction. It must, therefore, be used with caution in patients with suspected coronary artery disease .

Warning 1

The “hyperdynamic” circulation caused by hydralazine may accentuate specific cardiovascular inadequacies. For example, hydralazine may increase pulmonary artery pressure in patients with mitral valvular disease. The drug may reduce the pressor responses to epinephrine. Postural hypotension may result from hydralazine but is less common than with ganglionic blocking agents. It should be used with caution in patients with cerebral vascular accidents.

Warning 2

In hypertensive patients with normal kidneys who are treated with hydralazine, there is evidence of increased renal blood flow and a maintenance of glomerular filtration rate. In some instances where control values were below normal, improved renal function has been noted after administration of hydralazine. However, as with any antihypertensive agent, hydralazine should be used with caution in patients with advanced renal damage.

Warning 3

You can drive while taking Hydralazine but do not drive until you know how the medicine affect you. They may make you feel dizzy. If they affect you in this way, do not drive or operate any machinery .

Pregnancy category

Always consult your physician before using any medicine.

Storage (YES/NO)

Store this medicine at room temperature, away from direct light and heat.