Prazosin Hydrochloride 1 mg Capsule, 30-count
Other active recalls for Prazosin Hydrochloride (different manufacturers) — 6 · tap to view
🆔 Identity & classification
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🏷️ RxNorm drug class
This medicine belongs to the alpha-Adrenergic Blocker class.
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🏭 Manufacturer & labeler
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🩺 Clinical
Prazosin is used to treat high blood pressure. Prazosin is in a class of medications called alpha-blockers. It works by relaxing the blood vessels so that blood can flow more easily through the body. High blood pressure is a common condition and when not treated, can cause damage to the brain, heart, blood vessels, kidneys, and other parts of the body. Damage to these organs may cause heart disease, a heart attack, heart failure, stroke, kidney failure, loss of vision, and other problems. In addition to taking medication, making lifestyle changes will also help to control your blood pressure....
Read the full MedlinePlus article ↗- 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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💊 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.
💡 Tap an ingredient (hover on desktop) to see what it is and why it’s used.
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UNII 5138Q19F1X
Ammonia is a colorless gas made from nitrogen and hydrogen. It's used in medicines as a pH buffer to maintain the correct acidity level and help keep the product stable.
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UNII 3SY5LH9PMK
Anhydrous lactose is a milk sugar with no water content. It acts as a filler and binder in tablets and capsules, adding bulk and helping ingredients stick together.
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UNII XM0M87F357
A dark iron oxide compound that gives medicines their black or dark color. It's used as a colorant in tablets and capsules to help identify the product and make it visually distinctive.
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UNII 2G86QN327L
Gelatin is a protein derived from animal collagen, commonly used in medicines as a gelling agent and capsule material. It helps create soft or hard capsule shells that hold and release medication, and can also thicken liquid formulations.
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UNII EWQ57Q8I5X
Lactose monohydrate is a natural sugar derived from milk. It serves as a filler and binder in tablets and capsules, helping create the proper size, texture, and consistency of the medicine.
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UNII 70097M6I30
Magnesium stearate is a salt made from magnesium and stearic acid, a fatty substance. It's used in tablets and capsules as a lubricant and glidant to help ingredients flow smoothly during manufacturing and prevent sticking.
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UNII OP1R32D61U
Microcrystalline cellulose is a purified form of cellulose, a natural fiber from plant sources. It acts as a binder and filler in tablets and capsules, helping hold ingredients together and give the medicine its shape and size.
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UNII 6DC9Q167V3
Propylene glycol is a clear liquid derived from petroleum or vegetable sources. It acts as a solvent, humectant, and preservative in medicines, helping dissolve active ingredients and maintain product stability.
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UNII 46N107B71O
Shellac is a natural resin secreted by the lac beetle. It's used as a coating on tablets and capsules to control how quickly the medicine dissolves and to improve appearance and stability.
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UNII 15FIX9V2JP
Titanium dioxide is a bright white mineral powder commonly used as a colorant and opacifying agent. It makes pills and tablets white or lighter in color and helps make coatings non-transparent.
10 inactive ingredients listed in the exact product block matched to this NDC.
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ingredient classCode="IACT" elements from the exact product block matched by this NDC. Label-section narrative from DailyMed / the openFDA label index is shown separately when available.Inactive ingredient FAQ
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💲 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 each | Per package |
|---|---|---|
| Retail pharmacies payNADAC · weekly | Not in the retail survey — common for institutional, discontinued, or low-volume packs. | |
| Medicaid paysCMS SDUD · 12 mo | No recent Medicaid claims on file for this NDC — rare and low-volume NDCs are suppressed in the public data. | |
| Medicare drug plans payPart D · Q2 2026 | $0.2217 | $6.65 / 30 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 mg 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 mgthis 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.
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🔬 Reported adverse events (FAERS)
Top reported reactions
Age at onset
Reporter sex
Serious outcomes
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📦 Packaging — all sizes for this product
| Package NDC | Description | Marketing start | Status |
|---|---|---|---|
| 71610-0693-30 You're viewing this | 30 CAPSULE in 1 BOTTLE (71610-693-30) | 2023-03-17 | Active |
| 71610-0693-53 | 60 CAPSULE in 1 BOTTLE (71610-693-53) | 2023-03-17 | Active |
| 71610-0693-60 | 90 CAPSULE in 1 BOTTLE (71610-693-60) | 2023-03-17 | Active |
| 71610-0693-80 | 180 CAPSULE in 1 BOTTLE (71610-693-80) | 2023-03-17 | Active |
You're viewing the smallest of 4 pack sizes for this product.
Pack size FAQ
What quantity is in NDC 71610-0693-30?
What is the difference between NDC 71610-0693-30 and NDC 71610-0693-53?
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🧭 About this NDC listing & data coverage
What data is (and isn’t) available for this NDC — tap to expand
| NDC identity (package / product / labeler codes) | ✓ Available |
| Labeler | ✓ Available |
| Product & package description | ✓ Available |
| Marketing category & status | ✓ Available |
| Active ingredient / dosage form / route | ✓ Available |
| FDA label (SPL via DailyMed) | ✓ Available |
| Package photos | ✓ Available |
| Inactive ingredients (structured) | ✓ Available |
| NADAC pharmacy acquisition price (CMS) | — Not published for this NDC CMS publishes NADAC only for NDCs reported in its retail-pharmacy survey. |
| Orange Book / therapeutic-equivalence data | ✓ Available |
| HCPCS J-code billing crosswalk | — Not published for this NDC Most self-administered / retail products have no J-code — that is normal. |
| Medicaid utilization (CMS SDUD) | — Not published for this NDC CMS reports utilization only for NDCs with Medicaid claims above its privacy threshold. |
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📄 Full prescribing information FDA SPL
🎯 Indications and Usage ▾
INDICATIONS AND USAGE Prazosin hydrochloride capsules, USP 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, USP 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 capsules 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 capsules should be reduced to 1 mg or 2 mg three times a day and retitration then carried out. Concomitant administration of prazosin hydrochloride capsules 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 capsules.
⛔ 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 capsules 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 capsules.
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 capsules 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 light headedness. 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 capsules 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 capsules 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).
🔄 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.
🧒 Pediatric Use ▾
Usage in Children Safety and effectiveness in children have not been established.
🆘 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 as follows: 1 mg Hard gelatin capsules, white opaque cap printed with "GPI (over) 1 mg" and white opaque body printed with "084" contains white to off-white blend. Bottles of 100 76282-721-01 Bottles of 1000 76282-721-10 2 mg Hard gelatin capsules, pink opaque cap printed with "GPI (over) 2 mg" and white opaque body printed with "085" contains white to off-white blend. Bottles of 100 76282-722-01 Bottles of 1000 76282-722-10 5 mg Hard gelatin capsules, dark blue opaque cap printed with "GPI (over) 5 mg" and white opaque body printed with "086" contains white to off-white blend.
Bottles of 100 76282-723-01 Bottles of 250 76282-723-25 Store at 20° to 25°C (68° to 77°F) [See USP Controlled Room Temperature]. Protect from light and moisture. Dispense in a tight, light-resistant container as defined in the USP with a child-resistant closure.
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: Granules Pharmaceuticals Inc., Chantilly, VA 20151 Manufactured for: Exelan Pharmaceuticals Inc. Boca Raton, FL 33432 21096466 LB0045-00 Rev. 10/2022
📋 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-dimethoxy2-quinazolinyl)-4-(2-furoyl) piperazine and its structural formula is: It is a white, crystalline substance, very slightly soluble in water, slightly soluble in methanol, dimethylformamide, dimethylacetamide and alcohol, practically insoluble in chloroform and acetone, and 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.
Inactive ingredients in the formulations are: anhydrous lactose, lactose monohydrate, magnesium stearate and silicified microcrystalline cellulose. The empty gelatin capsules contain gelatin and titanium dioxide; the 2 mg capsules contain FD&C red # 3 and FD&C blue # 1 and the 5 mg capsules contain FD&C Red # 40 and FD&C Blue # 1. In addition, capsule imprinting ink contains ammonium hydroxide, black iron oxide, propylene glycol and shellac glaze.
Meets USP Dissolution Test 2. 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, light headedness, 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 capsules, 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.