PRAZOSIN HYDROCHLORIDE 1 mg Capsule, 100-count
Other active recalls for Prazosin Hydrochloride (different manufacturers) — 6 · tap to view
🆔 Identity & classification
Where does this data come from?
🏷️ RxNorm drug class
This medicine belongs to the alpha-Adrenergic Blocker class.
Where does this data come from?
🏭 Manufacturer & labeler
Where does this data come from?
🩺 Clinical
- Prazosin is used to treat high blood pressure (hypertension). By lowering your blood pressure, it helps reduce your risk of serious problems like stroke and heart attack. It can be...
- Unfortunately, that's a known risk, especially with the first dose. Prazosin can cause a sudden drop in blood pressure — most likely in the 30 to 90 minutes after taking it — which...
- I felt really dizzy and almost fainted after my first dose. Is that normal?
- The biggest ones to know about are erectile dysfunction drugs — like sildenafil (Viagra) — and other blood pressure medications or water pills. These can make prazosin's blood pres...
Patient education
Supplement & herbal interactions
Prazosin may be associated with lower levels of 1 nutrient — worth a chat with your pharmacist, not a cause for alarm.
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Ask a licensed pharmacist directly — free, answered by our team.
💊 What it looks like
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🧪 Inactive Ingredients / Excipients
Inactive ingredients, also called excipients, are components of the drug product other than the active ingredient. They may include fillers, dyes, coatings, preservatives, flavors, or other formulation ingredients.
Where does this data come from?
IACT rows and label-wide narrative are kept separate; availability and product-level specificity depend on the submitted label.Inactive ingredient FAQ
Are inactive ingredients the same for every manufacturer?
Why might an inactive ingredient be missing?
Can inactive ingredients matter?
💲 Pricing
A drug doesn't have one price. Each row is a different public payment system, and none is what you'd pay at the counter — that depends on your insurance. The ⓘ on each row explains what it measures.
| Price system | Per ea | Per package |
|---|---|---|
| Retail pharmacies payNADAC · weekly | $0.086 | $8.58 / 100 capsules |
| Medicaid paysCMS SDUD · 12 mo | $0.2355 | $23.55 / 100 capsules |
| Medicare drug plans payPart D · Q2 2026 | $0.2217 | $22.17 / 100 capsules |
Where does this data come from?
🔁 Therapeutic equivalents
| Product | Labeler | Pack | NADAC/unit | TE | Status | Price vs. this |
|---|---|---|---|---|---|---|
| Prazosin Hydrochloride 1 mg 00093-4067-01 | Teva | 100 capsules | $0.086 | AB | Availability likely | — |
| Prazosin Hydrochloride 1 mg 00378-1101-01 | Mylan | 100 capsules | $0.086 | AB | Availability likely | — |
| Prazosin Hydrochloride 1 mg 00904-7020-61 | Major | 100 capsules | $0.086 | AB | Availability likely | — |
| Prazosin Hydrochloride 1 mg 51079-0630-20 | Mylan | 100 capsules | $0.086 | AB | Availability likely | — |
| Prazosin Hydrochloride 1 mg 59651-0271-01 | Aurobindo | 100 capsules | $0.086 | AB | Availability likely | — |
| Prazosin Hydrochloride 1 mgthis 62332-0691-31 | Alembic | 100 capsules | $0.086 | AB | Availability likely | — |
| Prazosin Hydrochloride 1 mg 66993-0431-85 | Prasco | 90 capsules | $0.086 | AB | Availability likely | — |
| Prazosin Hydrochloride 1 mg 68084-0996-01 | American | 100 capsules | $0.086 | AB | Availability likely | — |
| Prazosin Hydrochloride 1 mg 70010-0084-01 | Granules | 100 capsules | $0.086 | AB | Availability likely | — |
| Prazosin hydrochloride 1 mg 70377-0066-11 | Biocon | 100 capsules | $0.086 | AB | Availability likely | — |
| prazosin hydrochloride 1 mg 70756-0429-11 | Lifestar | 100 capsules | $0.086 | AB | Availability likely | — |
| Prazosin Hydrochloride 1 mg 70954-0019-10 | ANI | 100 capsules | $0.086 | AB | Availability likely | — |
| prazosin hydrochloride 1 mg 72205-0275-90 | Novadoz | 90 capsules | $0.086 | AB | Availability likely | — |
| Prazosin Hydrochloride 1 mg 76282-0721-01 | Exelan | 100 capsules | $0.086 | AB | Availability likely | — |
| Prazosin 1 mg 00527-4180-37 | Lannett | 100 capsules | — | — | FDA listed | — |
| Prazosin Hydrochloride 1 mg 00615-8519-39 | NCS | 30 capsules | — | AB | FDA listed | — |
| Prazosin Hydrochloride 1 mg 10135-0666-01 | Marlex | 100 capsules | — | AB | FDA listed | — |
| Prazosin Hydrochloride 1 mg 46708-0691-31 | Alembic | 100 capsules | — | AB | FDA listed | — |
| Prazosin Hydrochloride 1 mg 48433-0084-20 | Safecor | 100 capsules | — | AB | FDA listed | — |
| Prazosin Hydrochloride 1 mg 50090-5695-00 | A-S | 100 capsules | — | AB | FDA listed | — |
| Prazosin Hydrochloride 1 mg 55154-4156-00 | Cardinal | 10 capsules | — | AB | FDA listed | — |
| Prazosin Hydrochloride 1 mg 55154-8181-00 | Cardinal | 10 capsules | — | AB | FDA listed | — |
| Prazosin Hydrochloride 1 mg 55289-0536-60 | PD-Rx | 60 capsules | — | AB | FDA listed | — |
| prazosin hydrochloride 1 mg 60760-0820-30 | ST. | 30 capsules | — | AB | FDA listed | — |
| Prazosin Hydrochloride 1 mg 63629-8750-01 | Bryant | 1000 capsules | — | AB | FDA listed | — |
| Prazosin Hydrochloride 1 mg 63629-8756-01 | Bryant | 100 capsules | — | AB | FDA listed | — |
| Prazosin Hydrochloride 1 mg 67046-0680-03 | Coupler | 30 capsules | — | AB | FDA listed | — |
| Prazosin Hydrochloride 1 mg 68788-7335-01 | Preferred | 100 capsules | — | AB | FDA listed | — |
| Prazosin Hydrochloride 1 mg 70518-3271-00 | REMEDYREPACK | 30 capsules | — | AB | FDA listed | — |
| prazosin hydrochloride 1 mg 70518-3669-00 | REMEDYREPACK | 60 capsules | — | AB | Discontinued | — |
| Prazosin hydrochloride 1 mg 70518-3928-00 | REMEDYREPACK | 30 capsules | — | AB | FDA listed | — |
| Prazosin Hydrochloride 1 mg 70518-4457-00 | REMEDYREPACK | 30 capsules | — | AB | FDA listed | — |
| Prazosin Hydrochloride 1 mg 70518-4489-00 | REMEDYREPACK | 30 capsules | — | AB | FDA listed | — |
| Prazosin Hydrochloride 1 mg 71335-1401-01 | Bryant | 30 capsules | — | AB | Discontinued | — |
| Prazosin Hydrochloride 1 mg 71335-1724-01 | Bryant | 30 capsules | — | AB | FDA listed | — |
| prazosin hydrochloride 1 mg 71335-9648-01 | Bryant | 30 capsules | — | AB | FDA listed | — |
| Prazosin Hydrochloride 1 mg 71610-0693-30 | Aphena | 30 capsules | — | AB | FDA listed | — |
| Prazosin HCL 1 mg 72189-0436-30 | Direct_Rx | 30 capsules | — | AB | FDA listed | — |
| prazosin hydrochloride 1 mg 76420-0523-01 | ASCLEMED | 100 capsules | — | AB | FDA listed | — |
| Prazosin Hydrochloride 1 mg 87441-0067-01 | Unit | 30 capsules | — | AB | FDA listed | — |
| prazosin hydrochloride 1 mg 70518-4712-00 | REMEDYREPACK | 30 capsules | — | AB | FDA listed | — |
Where does this data come from?
⏳ Availability & generic status
This product is an FDA-approved generic. Other versions of the same drug are listed under Therapeutic equivalents, least expensive first.
Where does this data come from?
🗺️ Medicaid utilization & spend
💊 Medicaid utilization by pack size
🔬 Reported adverse events (FAERS)
Top reported reactions
Age at onset
Reporter sex
Serious outcomes
Where does this data come from?
📦 Packaging — all sizes for this product
| Package NDC | Description | Per unit | Per pack | Marketing start | Status |
|---|---|---|---|---|---|
| 62332-0691-31 You're viewing this | 100 CAPSULE in 1 BOTTLE (62332-691-31) | $0.0858 / ea | $8.58 | 2023-03-09 | Active |
| 62332-0691-61 | 250 CAPSULE in 1 BOTTLE (62332-691-61) | — | — | 2023-03-09 | Active |
| 62332-0691-91 | 1000 CAPSULE in 1 BOTTLE (62332-691-91) | — | — | 2023-03-09 | Active |
You're viewing the smallest of 3 pack sizes for this product.
In Medicaid, this is the most-dispensed pack of this product — about 100% of fills over the last four reported quarters. See all packs ↓
Pack size FAQ
What quantity is in NDC 62332-0691-31?
What is the difference between NDC 62332-0691-31 and NDC 62332-0691-61?
What NDC number is used to bill for this package of PRAZOSIN HYDROCHLORIDE 1 mg Capsule?
Prices are the latest CMS NADAC pharmacy acquisition cost per NDC; per-pack figures are per-unit × pack quantity, shown only when the pack is denominated in the same measure NADAC prices.
📄 Full prescribing information FDA SPL
🎯 Indications and Usage ▾
INDICATIONS AND USAGE 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.
⏱️ Dosage and Administration ▾
DOSAGE AND ADMINISTRATION The dose of prazosin hydrochloride should be adjusted according to the patient’s individual blood pressure response. The following is a guide to its administration: Initial Dose 1 mg two or three times a day (see WARNINGS.) Maintenance Dose Dosage may be slowly increased to a total daily dose of 20 mg given in divided doses. The therapeutic dosages most commonly employed have ranged from 6 mg to 15 mg daily given in divided doses.
Doses higher than 20 mg usually do not increase efficacy, however a few patients may benefit from further increases up to a daily dose of 40 mg given in divided doses. After initial titration some patients can be maintained adequately on a twice daily dosage regimen. Use With Other Drugs When adding a diuretic or other antihypertensive agent, the dose of prazosin hydrochloride should be reduced to 1 mg or 2 mg three times a day and retitration then carried out.
Concomitant administration of prazosin hydrochloride with a PDE-5 inhibitor can result in additive blood pressure lowering effects and symptomatic hypotension; therefore, PDE-5 inhibitor therapy should be initiated at the lowest dose in patients taking prazosin hydrochloride.
⛔ Contraindications ▾
CONTRAINDICATIONS Prazosin hydrochloride capsules are contraindicated in patients with known sensitivity to quinazolines, prazosin, or any of the inert ingredients.
⚠️ Warnings ▾
WARNINGS As with all alpha-blockers, prazosin hydrochloride may cause syncope with sudden loss of consciousness. In most cases, this is believed to be due to an excessive postural hypotensive effect, although occasionally the syncopal episode has been preceded by a bout of severe tachycardia with heart rates of 120 to 160 beats per minute. Syncopal episodes have usually occurred within 30 to 90 minutes of the initial dose of the drug; occasionally, they have been reported in association with rapid dosage increases or the introduction of another antihypertensive drug into the regimen of a patient taking high doses of prazosin hydrochloride.
The incidence of syncopal episodes is approximately 1% in patients given an initial dose of 2 mg or greater. Clinical trials conducted during the investigational phase of this drug suggest that syncopal episodes can be minimized by limiting the initial dose of the drug to 1 mg, by subsequently increasing the dosage slowly, and by introducing any additional antihypertensive drugs into the patient’s regimen with caution (see DOSAGE AND ADMINISTRATION). Hypotension may develop in patients given prazosin hydrochloride who are also receiving a beta-blocker such as propranolol.
If syncope occurs, the patient should be placed in the recumbent position and treated supportively as necessary. This adverse effect is self-limiting and in most cases does not recur after the initial period of therapy or during subsequent dose titration. Patients should always be started on the 1 mg capsules of prazosin hydrochloride.
The 2 and 5 mg capsules are not indicated for initial therapy. More common than loss of consciousness are the symptoms often associated with lowering of the blood pressure, namely, dizziness and lightheadedness. The patient should be cautioned about these possible adverse effects and advised what measures to take should they develop.
The patient should also be cautioned to avoid situations where injury could result should syncope occur during the initiation of prazosin hydrochloride therapy. Priapism Prolonged erections and priapism have been reported with alpha-1 blockers including prazosin in post marketing experience. In the event of an erection that persists longer than 4 hours, seek immediate medical assistance.
If priapism is not treated immediately, penile tissue damage and permanent loss of potency could result.
🤒 Adverse Reactions ▾
ADVERSE REACTIONS Clinical trials were conducted on more than 900 patients. During these trials and subsequent marketing experience, the most frequent reactions associated with prazosin hydrochloride therapy are: dizziness 10.3%, headache 7.8%, drowsiness 7.6%, lack of energy 6.9%, weakness 6.5%, palpitations 5.3%, and nausea 4.9%. In most instances, side effects have disappeared with continued therapy or have been tolerated with no decrease in dose of drug.
Less frequent adverse reactions which are reported to occur in 1 to 4% of patients are: Gastrointestinal: vomiting, diarrhea, constipation. Cardiovascular: edema, orthostatic hypotension, dyspnea, syncope. Central Nervous System: vertigo, depression, nervousness.
Dermatologic: rash. Genitourinary: urinary frequency. EENT: blurred vision, reddened sclera, epistaxis, dry mouth, nasal congestion.
In addition, fewer than 1% of patients have reported the following (in some instances, exact causal relationships have not been established): Gastrointestinal: abdominal discomfort and/or pain, liver function abnormalities, pancreatitis. Cardiovascular: tachycardia. Central Nervous System: paresthesia, hallucinations.
Dermatologic: pruritus, alopecia, lichen planus. Genitourinary: incontinence, impotence, priapism. EENT: tinnitus.
Other: diaphoresis, fever, positive ANA titer, arthralgia. Single reports of pigmentary mottling and serous retinopathy, and a few reports of cataract development or disappearance have been reported. In these instances, the exact causal relationship has not been established because the baseline observations were frequently inadequate.
In more specific slit-lamp and funduscopic studies, which included adequate baseline examinations, no drug-related abnormal ophthalmological findings have been reported. Literature reports exist associating prazosin hydrochloride therapy with a worsening of pre-existing narcolepsy. A causal relationship is uncertain in these cases.
In post-marketing experience, the following adverse events have been reported: Autonomic Nervous System: flushing. Body As A Whole: allergic reaction, asthenia, malaise, pain. Cardiovascular, General: angina pectoris, hypotension.
Endocrine: gynecomastia. Heart Rate/Rhythm: bradycardia. Psychiatric: insomnia.
Skin/Appendages: urticaria. Vascular (Extracardiac): vasculitis. Vision: eye pain.
Special Senses: During cataract surgery, a variant of small pupil syndrome known as Intraoperative Floppy Iris Syndrome (IFIS) has been reported in association with alpha-1 blocker therapy (see PRECAUTIONS). To report SUSPECTED ADVERSE REACTIONS, contact Alembic Pharmaceuticals Limited at 1-866-210-9797 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.
🔄 Drug Interactions ▾
Drug Interactions Prazosin hydrochloride has been administered without any adverse drug interaction in limited clinical experience to date with the following: (1) cardiac glycosides– digitalis and digoxin; (2) hypoglycemics–insulin, chlorpropamide, phenformin, tolazamide, and tolbutamide; (3) tranquilizers and sedatives–chlordiazepoxide, diazepam, and phenobarbital; (4) antigout– allopurinol, colchicine, and probenecid; (5) antiarrhythmics–procainamide, propranolol (see WARNINGS however), and quinidine; and (6) analgesics, antipyretics and anti-inflammatories – propoxyphene, aspirin, indomethacin, and phenylbutazone.
Addition of a diuretic or other antihypertensive agent to prazosin hydrochloride has been shown to cause an additive hypotensive effect. This effect can be minimized by reducing the prazosin hydrochloride dose to 1 to 2 mg three times a day, by introducing additional antihypertensive drugs cautiously, and then by retitrating prazosin hydrochloride based on clinical response. Concomitant administration of prazosin hydrochloride with a phosphodiesterase-5 (PDE-5) inhibitor can result in additive blood pressure lowering effects and symptomatic hypotension (see DOSAGE AND ADMINISTRATION).
🔄 Drug / Laboratory Test Interactions ▾
Drug/Laboratory Test Interactions In a study on five patients given from 12 to 24 mg of prazosin per day for 10 to 14 days, there was an average increase of 42% in the urinary metabolite of norepinephrine and an average increase in urinary VMA of 17%. Therefore, false positive results may occur in screening tests for pheochromocytoma in patients who are being treated with prazosin. If an elevated VMA is found, prazosin should be discontinued and the patient retested after a month.
Laboratory Tests In clinical studies in which lipid profiles were followed, there were generally no adverse changes noted between pre- and post-treatment lipid levels.
🤰 Pregnancy ▾
Usage in Pregnancy: Prazosin hydrochloride has been shown to be associated with decreased litter size at birth, 1, 4, and 21 days of age in rats when given doses more than 225 times the usual maximum recommended human dose. No evidence of drug-related external, visceral, or skeletal fetal abnormalities were observed. No drug-related external, visceral, or skeletal abnormalities were observed in fetuses of pregnant rabbits and pregnant monkeys at doses more than 225 times and 12 times the usual maximum recommended human dose, respectively.
The use of prazosin and a beta-blocker for the control of severe hypertension in 44 pregnant women revealed no drug-related fetal abnormalities or adverse effects. Therapy with prazosin was continued for as long as 14 weeks. 1 Prazosin has also been used alone or in combination with other hypotensive agents in severe hypertension of pregnancy by other investigators.
No fetal or neonatal abnormalities have been reported with the use of prazosin. 2 There are no adequate and well controlled studies which establish the safety of prazosin hydrochloride in pregnant women. Prazosin hydrochloride should be used during pregnancy only if the potential benefit justifies the potential risk to the mother and fetus.
🆘 Overdosage ▾
OVERDOSAGE Accidental ingestion of at least 50 mg of prazosin hydrochloride in a two year old child resulted in profound drowsiness and depressed reflexes. No decrease in blood pressure was noted. Recovery was uneventful.
Should overdosage lead to hypotension, support of the cardiovascular system is of first importance. Restoration of blood pressure and normalization of heart rate may be accomplished by keeping the patient in the supine position. If this measure is inadequate, shock should first be treated with volume expanders.
If necessary, vasopressors should then be used. Renal function should be monitored and supported as needed. Laboratory data indicate prazosin hydrochloride is not dialysable because it is protein bound.
🧬 Clinical Pharmacology ▾
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 antihypertensive action of prazosin is usually not accompanied by a reflex tachycardia. Tolerance has not been observed to develop in long term therapy.
Hemodynamic studies have been carried out in man following acute single dose administration and during the course of long term maintenance therapy. The results confirm that the therapeutic effect is a fall in blood pressure unaccompanied by a clinically significant change in cardiac output, heart rate, renal blood flow and glomerular filtration rate. There is no measurable negative chronotropic effect.
In clinical studies to date, prazosin hydrochloride has not increased plasma renin activity. In man, blood pressure is lowered in both the supine and standing positions. This effect is most pronounced on the diastolic blood pressure.
Following oral administration, human plasma concentrations reach a peak at about three hours with a plasma half-life of two to three hours. The drug is highly bound to plasma protein. Bioavailability studies have demonstrated that the total absorption relative to the drug in a 20% alcoholic solution is 90%, resulting in peak levels approximately 65% of that of the drug in solution.
Animal studies indicate that prazosin hydrochloride is extensively metabolized, primarily by demethylation and conjugation, and excreted mainly via bile and feces. Less extensive human studies suggest similar metabolism and excretion in man. In clinical studies in which lipid profiles were followed, there were generally no adverse changes noted between pre- and post-treatment lipid levels.
📦 How Supplied / Storage and Handling ▾
HOW SUPPLIED Prazosin hydrochloride capsules, USP are available containing prazosin hydrochloride, USP equivalent to 1 mg, 2 mg, or 5 mg of prazosin. The 1 mg capsule is opaque white cap/opaque white body hard gelatin capsules size “4” having imprinting “A” on cap with black ink and “320” on body with black ink filled with white to off white granular powder. They are available as follows: Bottle of 100 capsules with child-resistant closure, NDC 62332-691-31 Bottle of 250 capsules, NDC 62332-691-61 Bottle of 1000 capsules, NDC 62332-691-91 The 2 mg capsule is opaque pink cap/opaque white body hard gelatin capsules size “2” having imprinting “A” on cap with black ink and “321” on body with black ink filled with white to off white granular powder.
They are available as follows: Bottle of 100 capsules with child-resistant closure, NDC 62332-692-31 Bottle of 250 capsules, NDC 62332-692-61 Bottle of 1000 capsules, NDC 62332-692-91 The 5 mg capsule is opaque blue cap/opaque white body hard gelatin capsules size “0” having imprinting “A” on cap with black ink and “322” on body with black ink filled with white to off white granular powder. They are available as follows: Bottle of 100 capsules with child-resistant closure, NDC 62332-693-31 Bottle of 250 capsules, NDC 62332-693-61 Bottle of 1000 capsules, NDC 62332-693-91 Store at 25°C (77°F); excursions permitted to 15° to 30°C (59° to 86°F) [see USP Controlled Room Temperature].
Dispense in a tight, light-resistant containers (USP). References 1. Lubbe, WF, and Hodge, JV: New Zealand Med J, 94 (691) 169–172, 1981.
2. Davey, DA, and Dommisse, J: S.A. Med J , Oct.
4, 1980 (551–556). Manufactured by: Alembic Pharmaceuticals Limited (Formulation Division), Panelav 389350, Gujarat, India Manufactured for: Alembic Pharmaceuticals Limited Bedminster, NJ 07921, USA Revised: 05/2023
📋 Description ▾
DESCRIPTION Prazosin hydrochloride, 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: Molecular formula C 19 H 21 N 5 O 4• HCl It is a white to tan powder, slightly soluble in methanol, in dimethyl formamide, in dimethyl acetamide, very slightly soluble in alcohol, practically insoluble in chloroform and in acetone. It has a molecular weight of 419.87.
Each capsule for oral administration contains prazosin hydrochloride, USP equivalent to 1 mg, 2 mg or 5 mg of prazosin. Inert ingredients in the formulations are: sucrose, corn starch, sodium lauryl sulfate, microcrystalline cellulose, colloidal silicon dioxide and magnesium stearate. The empty hard gelatin capsule shell contains gelatin and titanium dioxide.
In addition, the 2 mg and 5 mg empty hard gelatin capsule shell also contain FD&C Blue 1 and FD&C Red 3. The empty hard gelatin capsule shells are imprinted with edible black ink containing shellac, potassium hydroxide and black iron oxide. Prazosin hydrochloride capsules, USP meets USP Dissolution Test 3 . structure
💬 Information for Patients ▾
Information for Patients: Dizziness or drowsiness may occur after the first dose of this medicine. Avoid driving or performing hazardous tasks for the first 24 hours after taking this medicine or when the dose is increased. Dizziness, lightheadedness, or fainting may occur, especially when rising from a lying or sitting position.
Getting up slowly may help lessen the problem. These effects may also occur if you drink alcohol, stand for long periods of time, exercise, or if the weather is hot. While taking prazosin hydrochloride, be careful in the amount of alcohol you drink.
Also, use extra care during exercise or hot weather, or if standing for long periods. Check with your physician if you have any questions.