PRAZOSIN HYDROCHLORIDE capsule

Country: United States

Language: English

Source: NLM (National Library of Medicine)

Active ingredient:

PRAZOSIN HYDROCHLORIDE (UNII: X0Z7454B90) (PRAZOSIN - UNII:XM03YJ541D)

Available from:

Mylan Pharmaceuticals Inc.

INN (International Name):

PRAZOSIN HYDROCHLORIDE

Composition:

PRAZOSIN 1 mg

Administration route:

ORAL

Prescription type:

PRESCRIPTION DRUG

Therapeutic indications:

Prazosin hydrochloride capsules are indicated for the treatment of hypertension, to lower blood pressure. Lowering blood pressure reduces the risk of fatal and nonfatal cardiovascular events, primarily strokes and myocardial infarctions. These benefits have been seen in controlled trials of antihypertensive drugs from a wide variety of pharmacologic classes, including this drug. Control of high blood pressure should be part of comprehensive cardiovascular risk management, including, as appropriate, lipid control, diabetes management, antithrombotic therapy, smoking cessation, exercise, and limited sodium intake. Many patients will require more than one drug to achieve blood pressure goals. For specific advice on goals and management, see published guidelines, such as those of the National High Blood Pressure Education Program’s Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC). Numerous antihypertensive drugs, from a variety of pharmacologic classes and with different mechanisms of action, have been shown in randomized controlled trials to reduce cardiovascular morbidity and mortality, and it can be concluded that it is blood pressure reduction, and not some other pharmacologic property of the drugs, that is largely responsible for those benefits. The largest and most consistent cardiovascular outcome benefit has been a reduction in the risk of stroke, but reductions in myocardial infarction and cardiovascular mortality also have been seen regularly. Elevated systolic or diastolic pressure causes increased cardiovascular risk, and the absolute risk increase per mmHg is greater at higher blood pressures, so that even modest reductions of severe hypertension can provide substantial benefit. Relative risk reduction from blood pressure reduction is similar across populations with varying absolute risk, so the absolute benefit is greater in patients who are at higher risk independent of their hypertension (for example, patients with diabetes or hyperlipidemia), and such patients would be expected to benefit from more aggressive treatment to a lower blood pressure goal. Some antihypertensive drugs have smaller blood pressure effects (as monotherapy) in black patients, and many antihypertensive drugs have additional approved indications and effects (e.g., on angina, heart failure, or diabetic kidney disease). These considerations may guide selection of therapy. Prazosin hydrochloride capsules can be used alone or in combination with other antihypertensive drugs such as diuretics or beta-adrenergic blocking agents. Prazosin hydrochloride capsules are contraindicated in patients with known sensitivity to quinazolines, prazosin, or any of the inert ingredients.

Product summary:

Prazosin Hydrochloride Capsules, USP are available containing prazosin hydrochloride, USP equivalent to 1 mg, 2 mg, or 5 mg of prazosin. The 1 mg capsules are hard-shell gelatin capsules with a dark green opaque cap and a light brown opaque body filled with a white to off-white powder blend. The capsule is axially printed with MYLAN over 1101 in white ink on both the cap and body. They are available as follows: NDC 0378-1101-01 bottles of 100 capsules NDC 0378-1101-10 bottles of 1000 capsules The 2 mg capsules are hard-shell gelatin capsules with a brown opaque cap and a light brown opaque body filled with a white to off-white powder blend. The capsule is axially printed with MYLAN over 2302 in white ink on both the cap and body. They are available as follows: NDC 0378-2302-01 bottles of 100 capsules NDC 0378-2302-10 bottles of 1000 capsules The 5 mg capsules are hard-shell gelatin capsules with a light blue opaque cap and a light brown opaque body filled with a white to off-white powder blend. The capsule is axially printed with MYLAN over 3205 in white ink on both the cap and body. They are available as follows: NDC 0378-3205-01 bottles of 100 capsules NDC 0378-3205-25 bottles of 250 capsules Store at 20° to 25°C (68° to 77°F). [See USP Controlled Room Temperature.] Protect from moisture and light. Dispense in a tight, light-resistant container as defined by the USP using a child-resistant closure.

Authorization status:

Abbreviated New Drug Application

Summary of Product characteristics

PRAZOSIN HYDROCHLORIDE- PRAZOSIN HYDROCHLORIDE CAPSULE
MYLAN PHARMACEUTICALS INC.
----------
DESCRIPTION
Prazosin hydrochloride capsules, USP a quinazoline derivative, is the
first of a new
chemical class of antihypertensives. It is the hydrochloride salt of
1-(4-amino-6,7-
dimethoxy-2-quinazolinyl)-4-(2-furoyl) piperazine and its structural
formula is:
It is a white to tan powder, slightly soluble in water and methanol,
very slightly soluble in
alcohol, practically insoluble in chloroform and acetone and has a
molecular weight of
419.87. Each capsule, for oral use, contains prazosin hydrochloride,
USP equivalent (as
the polyhydrate) to 1 mg, 2 mg or 5 mg of prazosin.
MOLECULAR FORMULA C
H
N O • HCL
Inert ingredients in the formulations are: colloidal silicon dioxide,
lactose monohydrate,
magnesium stearate and microcrystalline cellulose. The empty gelatin
capsules contain
black iron oxide, gelatin, red iron oxide, titanium dioxide and yellow
iron oxide. In
addition, the 1 mg empty gelatin capsules contain D&C Yellow No. 10
and FD&C Green
No. 3; the 2 mg empty gelatin capsules contain D&C Red No. 28, D&C
Yellow No. 10,
FD&C Blue No. 1 and FD&C Red No. 40; and the 5 mg empty gelatin
capsules contain
FD&C Blue No. 1.
The imprinting ink also contains ammonium hydroxide, propylene glycol,
shellac glaze,
simethicone and titanium dioxide.
CLINICAL PHARMACOLOGY
The exact mechanism of the hypotensive action of prazosin is unknown.
Prazosin
causes a decrease in total peripheral resistance and was originally
thought to have a
direct relaxant action on vascular smooth muscle. Recent animal
studies, however, have
suggested that the vasodilator effect of prazosin is also related to
blockade of
postsynaptic alpha-adrenoceptors. The results of dog forelimb
experiments
demonstrate that the peripheral vasodilator effect of prazosin is
confined mainly to the
level of the resistance vessels (arterioles). Unlike conventional
alpha-blockers, the
19 21 5
4
antihypertensive action of prazosin is usually not accompanied by a
reflex ta