Prescription medication · Alpha-1 Adrenergic Blocker
doxazosin
Also sold as Cardura. Doxazosin is used to treat high blood pressure (hypertension).
Data updated 2026-05-15
- 27,049
- FDA reportsModerately reported
- 2
- InteractionsFew interactions
- 2
- Recall records
What the data shows
doxazosin (Cardura) is a prescription Alpha-1 Adrenergic Blocker, reported at a middle-of-the-pack volume (27,049 FDA reports), with 2 documented drug interactions.
Reporting volume reflects how widely a drug is used and studied, not how dangerous it is, a FAERS report documents a temporal association, never proof of cause.
doxazosin (Cardura) is a prescription Alpha-1 Adrenergic Blocker. Doxazosin is used to treat high blood pressure (hypertension).
Doxazosin is a medicine that can help lower high blood pressure and improve symptoms of an enlarged prostate in men.
Verify with FDA → · CMS NADAC pricing →
Drug Pricing (NADAC)
Generic Price
$0.07/unit
Generic Available
Yes (10 manufacturers)
Pricing data from NADAC (CMS), effective December 18, 2024. Compare all drug costs →
What it does
Doxazosin is used to treat high blood pressure (hypertension).
Common side effects
Dizziness, Feeling tired, Low blood pressure
Key warnings
Doxazosin can cause your blood pressure to drop suddenly when you stand up, leading to dizziness or fainting.
The sections below are summarized in plain English from doxazosin's FDA-approved prescribing information. They describe what the official label says, and are not personal medical advice.
How It Works
Doxazosin belongs to a class of drugs called alpha-1 adrenergic blockers. It works by relaxing the muscles in the prostate and bladder neck, making it easier to urinate. It also relaxes blood vessels, which helps to lower blood pressure.
How to Take It
Take doxazosin once a day, either in the morning or evening. You can take it with or without food. For BPH, the starting dose is 1 mg daily, which may be increased every 1 to 2 weeks up to 8 mg daily. For high blood pressure, the starting dose is 1 mg daily, which may be increased as needed up to 16 mg daily.
This is a plain-language summary of doxazosin's FDA labeling, not individualized dosing advice. Ask a pharmacist or prescriber before changing how you take this medication.
Pregnancy & Breastfeeding
It is not known if doxazosin can harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant. Doxazosin does pass into breast milk in small amounts. Talk to your doctor about the best way to feed your baby if you are taking doxazosin.
This is a plain-language summary of doxazosin's FDA labeling, not individualized advice. Ask a pharmacist or prescriber about pregnancy or breastfeeding on this medication.
Missed Dose
If you miss a dose, take it as soon as you remember. If it is close to the time for your next dose, skip the missed dose and continue with your regular schedule.
This is a plain-language summary of doxazosin's FDA labeling, not individualized advice. Ask a pharmacist or prescriber what to do about your specific missed dose.
Storage
Store doxazosin tablets at room temperature, away from heat and moisture.
Side Effects (from patient reports)
Based on 27,049 FDA adverse event reports.
Most-reported reactions
Adverse reactions in FAERS for doxazosin, by number of reports
- Shortness of breath
Shortness of breath
1,478 reports
- Feeling unsteady
Feeling unsteady
1,295 reports
- Feeling very tired
Feeling very tired
1,276 reports
- Loose stools
Loose stools
1,237 reports
- Sudden kidney damage
Sudden kidney damage
1,135 reports
- Feeling sick to your stomach
Feeling sick to your stomach
1,133 reports
- Low blood pressure
Low blood pressure
988 reports
- Weakness
Weakness
952 reports
- Pain in your head
Pain in your head
941 reports
- High blood pressure
High blood pressure
855 reports
What this shows Bars show how often each reaction was reported, not how likely it is to happen, a report records a temporal association, never proof that the drug caused it.
Reports over time
Adverse-event reports filed for doxazosin each year to the FDA Adverse Event Reporting System (FAERS).
Year-to-year volume tracks usage, prescribing, and scrutiny, not a change in per-patient risk. Source: FDA FAERS.
Where doxazosin sits
doxazosin has more FDA adverse-event reports than 61% of the drugs FAERS tracks. A high position reflects how widely a drug is used and watched, not how dangerous it is.
Percentile across all drugs PlainMeds tracks by FAERS report volume. The dot is doxazosin; the line is the median (50th percentile).
FDA Adverse Event Report Analysis
Detailed analysis of 27,049 reports from the FDA Adverse Event Reporting System (FAERS). Reports span 2003–2025.
Total Reports
27,049
Reports Mentioning Death
2,269
8.4% of reports — not proof of cause
Hospitalization Reports
11,467
Top Indication
Product Used For Unknown Indication
Gender Distribution
Age Distribution
Most Reported Adverse Reactions (FAERS)
| # | Reaction | Reports |
|---|---|---|
| 1 | DYSPNOEA | 1,479 |
| 2 | DIZZINESS | 1,295 |
| 3 | FATIGUE | 1,276 |
| 5 | DIARRHOEA | 1,237 |
| 6 | ACUTE KIDNEY INJURY | 1,135 |
| 7 | NAUSEA | 1,131 |
| 8 | HYPOTENSION | 988 |
| 9 | ASTHENIA | 950 |
| 10 | HEADACHE | 941 |
| 11 | HYPERTENSION | 853 |
| 12 | DRUG INTERACTION | 851 |
| 13 | VOMITING | 835 |
| 15 | RENAL FAILURE | 773 |
| 16 | MALAISE | 765 |
| 17 | FALL | 742 |
Reactions in Death Reports
Reactions in Hospitalization Reports
Source: FDA FAERS (Adverse Event Reporting System) FDA FAERS (Adverse Event Reporting System) Reports are voluntary and do not establish causation
Serious Warnings
Doxazosin can cause your blood pressure to drop suddenly when you stand up, leading to dizziness or fainting. This is more likely when you first start taking it or when the dose is increased. If you are having cataract surgery, tell your doctor you are taking this medicine. Doxazosin has been linked to priapism (a painful erection lasting for hours). If this happens, seek medical attention right away.
Known Drug Interactions
Postural hypotension has been reported in patients taking both beta-blockers and terazosin or doxazosin.
Mechanism: Both drugs lower blood pressure, which can cause a sudden drop in pressure when you stand up. This can make you feel dizzy or faint.
What to do: Stand up slowly from a sitting or lying position to avoid falling. Your doctor may need to adjust your medication doses.
Clinical pharmacology studies have been conducted with coadministration of tadalafil with doxazosin, tamsulosin or alfuzosin.
Mechanism: Both of these medications can lower your blood pressure, and taking them together might cause your blood pressure to drop too low.
What to do: Your doctor should monitor your blood pressure closely and may need to adjust your doses.
This is a plain-language summary of interactions documented in FDA labeling, not individualized advice. Ask a pharmacist or prescriber before combining medications.
Common Questions
Can I drink alcohol while taking doxazosin?
How long does it take for doxazosin to start working?
Can I stop taking doxazosin suddenly?
Does doxazosin affect my ability to drive or operate machinery?
Will doxazosin cure my enlarged prostate?
Can women take doxazosin?
What should I do if I feel dizzy after taking doxazosin?
Can I take doxazosin with other medications?
Will doxazosin affect my sexual function?
How often should I see my doctor while taking doxazosin?
What are the common side effects of doxazosin?
Does doxazosin interact with other medications?
What drug class is doxazosin?
Is doxazosin safe during pregnancy?
Has doxazosin been recalled?
Active Recalls
Tablets/Capsules Imprinted with Wrong ID
Unichem Pharmaceuticals USA Inc.
cGMP Deviations for the manufacturing Firm (Accord Healthcare) after their inspection.
Preferred Pharmaceuticals, Inc.
Related Medications in Alpha-1 Adrenergic Blocker
Other drugs grouped near doxazosin - same-class peers and common alternatives.
acebutolol
Sectral
Acebutolol is a medicine that helps lower blood pressure and control irregular heartbeats.
Compare with doxazosin →
aliskiren
Tekturna
Tekturna is a medicine used to treat high blood pressure.
Compare with doxazosin →
amiloride
Midamor
Amiloride is a water pill that helps your body hold onto potassium.
Compare with doxazosin →
amlodipine
Norvasc
Amlodipine (Norvasc) is a drug that lowers blood pressure and treats chest pain.
Compare with doxazosin →
amlodipine/benazepril
Lotrel
Lotrel is a combination medicine that contains amlodipine and benazepril.
Compare with doxazosin →
Medication Guides
Understanding Drug Interactions
How CYP450 enzymes, inhibitors, and inducers affect your medications
Generic vs Brand Name Drugs
FDA requirements, cost savings, and when the difference matters
Narrow Therapeutic Index Drugs
Why some drugs demand precise dosing and monitoring
Common Drug Interactions
Dangerous medication combinations and how to protect yourself
Save on doxazosin
Compare prices and find discounts at pharmacies near you. Free coupons can save up to 80% on prescriptions.
Disclosure: This link may earn us a commission at no extra cost to you. See our terms.
What the FDA Data Shows for doxazosin
The FDA label for doxazosin (sold under brand names such as Cardura) classifies it as a prescription-only medication in the Alpha-1 Adrenergic Blocker class. Doxazosin is used to treat high blood pressure (hypertension). Official labeling lists 6 commonly reported side effects, including Dizziness, Feeling tired, Low blood pressure.
Post-market surveillance from the FDA Adverse Event Reporting System (FAERS) captures real-world experience. For this drug, FAERS contains 27,049 voluntary reports. The database also lists 2 documented drug interactions derived from FDA labeling, with the top-flagged interaction rated minor severity. NADAC pricing from CMS shows a generic unit cost of $0.07.
Report counts do not establish causation, a FAERS entry documents a temporal association, not proof that the drug produced the outcome. Widely prescribed medications naturally accumulate more reports than niche therapies, so raw totals must be interpreted alongside total exposure. Shortage status, recall history (currently 2 recall records on file), and patent information further shape supply and switching decisions. This page summarizes public FDA data for educational purposes only and is not a substitute for professional medical advice, always consult a licensed healthcare provider before starting, stopping, or changing any medication.
Data Sources
Drug labeling: FDA Drug Labels (SPL/DailyMed). Adverse events: FDA Adverse Event Reporting System (FAERS). Pricing: CMS National Average Drug Acquisition Cost (NADAC).
FAERS reports are voluntary and do not establish causation. Drug interactions are derived from FDA labeling and clinical references. Always consult a healthcare professional before making medication decisions.
Last updated: March 31, 2025
Read our methodology - how this data is sourced, computed, and verified.
Data currency: FDA FAERS adverse-event reports through 2025, CMS NADAC acquisition-cost pricing effective December 2024, compiled and last refreshed May 2026. See our methodology for per-source dates and refresh cadence. Spot a figure that looks wrong? Report a correction.
All federal data sources used on this page
- FDA Orange Book - approved drug products with therapeutic equivalence. accessdata.fda.gov/cder/ob
- FDA DailyMed - NIH-hosted drug labeling for FDA-approved meds. dailymed.nlm.nih.gov
- FDA Adverse Event Reporting System (FAERS) - post-marketing safety surveillance. fda.gov/drugs/faers
- NLM RxNorm - standardized clinical drug nomenclature. nlm.nih.gov/research/umls/rxnorm
- CMS Medicare Part B Drug Average Sales Price Files - federal drug pricing data. cms.gov/medicare/part-b-drugs/asp
- FDA Drug Shortages Database - current and resolved drug shortage tracking. accessdata.fda.gov/drugshortages