Reported Reactions

Drugs › alpha-Adrenergic blocker

Generic name

Terazosin: adverse event reports filed with FDA

703 reports list it as a suspect or interacting product, 2004–2026. Class: alpha-Adrenergic blocker. Also reported as Terazosin 1mg, Terazosin 10mg, Terazosin 2mg.

703
reports as suspect product
0% of all reports · about 32 a year
22
reports, 12 months to June 2026
14 in the 12 months before
73.7%
marked serious by the reporter
76.2% across the class
8.7%
record death among outcomes, as reported
61 reports · not verified by FDA

703 adverse event reports received by FDA list terazosin, a generic name as a suspect or interacting product, from June 2004 to June 2026. A further 7,107 reports list it only as a concomitant medication, and those are not counted in the figures on this page.

In the 12 months to June 2026, 22 reports listed it, up 57% from 14 in the 12 months before. FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases. Over its reporting history that is about 32 reports a year and 0% of the 20,646,523 reports in the database, and 1.8% of the reports for the alpha-Adrenergic blocker class. How many people take it is not in the data, so a count is not a rate of occurrence.

The MedDRA terms listed most often are hypotension (11.7%), dizziness (11.1%) and drug ineffective (8.4%). A report can list several reactions, so shares add to more than 100%; 212 different terms appear across these reports. Hypotension is recorded in 11.7% of these reports, a larger share than in the median alpha-Adrenergic blocker drug (7.4%).

73.7% of the reports are marked serious by the reporter (76.2% across the class); 8.7% record death among the outcomes and 38.4% record hospitalisation, as reported. 24.8% of the reports came from pharmacists, and the largest patient age group is 75 and over (27.2%). FDA states that "a causal relationship cannot be established between product and reactions listed in a report" and that for any given report "there is no certainty that a suspected drug caused the event."

Reports by month, five years

059Jul 2021: 8Aug 2021: 1Sep 2021: 2Oct 2021: 0Nov 2021: 5Dec 2021: 42022Jan 2022: 5Feb 2022: 8Mar 2022: 6Apr 2022: 3May 2022: 3Jun 2022: 4Jul 2022: 1Aug 2022: 4Sep 2022: 1Oct 2022: 3Nov 2022: 3Dec 2022: 02023Jan 2023: 6Feb 2023: 0Mar 2023: 0Apr 2023: 2May 2023: 3Jun 2023: 7Jul 2023: 1Aug 2023: 1Sep 2023: 0Oct 2023: 0Nov 2023: 4Dec 2023: 02024Jan 2024: 4Feb 2024: 3Mar 2024: 1Apr 2024: 1May 2024: 2Jun 2024: 0Jul 2024: 3Aug 2024: 1Sep 2024: 1Oct 2024: 2Nov 2024: 2Dec 2024: 12025Jan 2025: 0Feb 2025: 1Mar 2025: 2Apr 2025: 0May 2025: 1Jun 2025: 0Jul 2025: 0Aug 2025: 9Sep 2025: 3Oct 2025: 1Nov 2025: 0Dec 2025: 52026Jan 2026: 2Feb 2026: 0Mar 2026: 0Apr 2026: 0May 2026: 1Jun 2026: 1

Reports by the month FDA received them. FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases.

By year received

038752004: 320042005: 752006: 202007: 320072008: 12011: 12012: 1720122013: 372014: 312015: 5220152016: 532017: 572018: 5420182019: 452020: 692021: 7320212022: 412023: 242024: 2120242025: 222026: 4

2026 covers reports received through June 2026 only.

Reactions recorded in the reports

share of Terazosin reports recording the termmedian drug in alpha-adrenergic blocker

  1. Hypotensionlow blood pressure11.7%82
  2. Dizzinesslight-headedness or unsteadiness11.1%78
  3. Drug ineffectivethe medicine did not work as expected8.4%59
  4. Syncopefainting7.4%52
  5. Drug interactionan interaction between medicines5.7%40
  6. Falla fall5.1%36
  7. Dyspnoeashortness of breath5%35
  8. Hypertensionhigh blood pressure4.7%33
  9. Drug hypersensitivityan allergic-type reaction to a medicine4.6%32
  10. Coughcough4.4%31
  11. Astheniaweakness or lack of energy4.1%29
  12. Completed suicidedeath by suicide4%28
  13. Hyperkalaemiahigh blood potassium3.7%26
  14. Chest discomfortchest discomfort3.6%25
  15. Nasopharyngitisa cold3.6%25
  16. Painpain, site not specified3.6%25
  17. Malaisegeneral feeling of being unwell3.4%24
  18. Asthmaasthma3.3%23
  19. Product use issuea problem in how the product was used3.3%23
  20. Toxicity to various agentspoisoning or toxic effect of one or more substances3.3%23
  21. Wheezingwheezing3.3%23
  22. Acute kidney injurysudden loss of kidney function3%21
  23. Bradycardiaslow heart rate2.8%20
  24. Renal failurekidney failure2.8%20
  25. Dysuriapain on passing urine2.6%18
  26. Fatiguetiredness2.6%18

Top 30 of 212 MedDRA preferred terms recorded across these reports, with a plain-language gloss where one is available. One report can record several terms. The hollow bar is the median share across the 12 drugs in the alpha-adrenergic blocker class; it describes the reports, not the patients. FDA states that adverse event reports "represent a small percentage of total usage numbers of a product", that "common products may have a higher number of adverse events due to the higher total number of people using the product", and that the data "by themselves are not an indicator of the safety profile of the drug or biologic."

Outcomes recorded

Death8.7%61
Life-threatening4.4%31
Hospitalisation (initial or prolonged)38.4%270
Disability2.1%15
Congenital anomaly0%0
Other serious43.4%305
Not serious26.3%185

Outcome flags as the reporter set them; a report can carry several, and "other serious" is FDA's own category for serious reports outside the named outcomes. Grey bar: all 38,454 reports in the class. FDA has not verified any outcome and states that the reports "cannot be used to estimate the incidence of these events."

Patients and reporters

Patient age

Under 20%0
2 to 110%0
12 to 170%0
18 to 443.8%27
45 to 6424%169
65 to 7418.8%132
75 and over27.2%191
Age not given26.2%184

Patient sex

Female23%162
Male67%471
Not given10%70

Who reported

Physician20.9%147
Pharmacist24.8%174
Other health professional24.3%171
Lawyer0%0
Consumer or non-health professional24.2%170
Not given5.8%41

Age and sex as stated in the report; the reporter's qualification is the primary source recorded by FDA. 72.8% of reports give the United States as the country of the event or reporter.

Reason for use recorded

Indication as recorded (MedDRA)ReportsShare
Hypertension10514.9%
Benign prostatic hyperplasia10414.8%
Prostatic disorder111.6%
Secondary hypertension91.3%
Prostatomegaly81.1%
Endocrine hypertension40.6%

The indication field is filled in by the reporter and is often blank; shares are of all 703 reports.

Drugs most often listed in the same reports

Drug (any role in the report)ReportsShare of Terazosin reports
Amlodipine9813.9%
Hydralazine7811.1%
Metoprolol7711%
Aspirin568%
Prednisone486.8%
Lisinopril466.5%
Simvastatin446.3%
Clonidine405.7%
Nifedipine365.1%
Carvedilol344.8%

Other products listed in reports where Terazosin is a suspect product, whatever their own role. Co-listing means the two were recorded together; it says nothing about either product's part in the event. Only the 2,500 most-reported names are counted here.

In context

MeasureTerazosinalpha-Adrenergic blockerAll reports
Reports as suspect product70338,45420,646,523
Share of that pool—1.8%0%
Reports, latest 12 months22—1,332,454
Marked serious73.7%76.2%57.4%
Death recorded among outcomes, per 1,000 reports8712191
Hospitalisation recorded, per 1,000 reports384370213
Consumer-filed share24.2%39.1%45.8%
Top term, share of reportsHypotension 11.7%median 7.4%1%

Shares are of reports, not of patients treated. The number of people taking a product is not in the data, so none of these figures is a rate, and differences between columns reflect who takes a product, who reports and how long it has been sold. FDA states that adverse event reports "represent a small percentage of total usage numbers of a product", that "common products may have a higher number of adverse events due to the higher total number of people using the product", and that the data "by themselves are not an indicator of the safety profile of the drug or biologic."

Other drugs in the alpha-adrenergic blocker class

DrugName typeReportsLatest 12 monthsMarked serious
Carvedilolgeneric14,16370083%
Tamsulosin hydrochloridegeneric5,44453985%
Coregbrand4,9892941.4%
Doxazosingeneric4,25134195.4%
Coreg CRbrand2,020329.3%
Cardurabrand1,8034184.7%
Doxazosin mesylategeneric1,7317692.4%
Prazosingeneric1,10511590.2%
Uroxatralbrand844139.3%
Silodosingeneric75510688.1%
Alfuzosin hydrochloridegeneric6465685.8%

Ordered by report count for navigation only. FDA states that adverse event reports "represent a small percentage of total usage numbers of a product", that "common products may have a higher number of adverse events due to the higher total number of people using the product", and that the data "by themselves are not an indicator of the safety profile of the drug or biologic." A brand and its generic are separate rows because reporters name them separately.

Questions about Terazosin reports

How many adverse event reports has FDA received for Terazosin?

703 reports list Terazosin as a suspect or interacting product in the openFDA FAERS release of 28 Sep 2026, covering reports received through June 2026. 22 of them arrived in the latest 12 months. Another 7,107 list it only as a concomitant medication.

What reactions are recorded in Terazosin reports?

hypotension (11.7%), dizziness (11.1%), drug ineffective (8.4%), syncope (7.4%) and drug interaction (5.7%). These are MedDRA preferred terms coded from what the reporter described; a report can list several, and a term's presence is not a finding that Terazosin was responsible.

How serious are the reports?

73.7% are marked serious by the reporter. Among the outcomes recorded, 8.7% of reports include death and 38.4% include hospitalisation. FDA has not verified these outcomes and states that the reports "cannot be used to estimate the incidence" of the events.

Who files these reports?

pharmacist (24.8%), other health professional (24.3%) and consumer or non-health professional (24.2%). Most reports reach FDA through the manufacturer, which must forward reports it receives.

Are reports for Terazosin rising?

22 reports in the 12 months to June 2026, up 57% from 14 in the 12 months before. FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases. Counts also move with how many people take a product, its time on the market and publicity.

Do these reports show that Terazosin was responsible for these reactions?

No. FDA states that "a causal relationship cannot be established between product and reactions listed in a report" and that for any given report "there is no certainty that a suspected drug caused the event." The reaction may relate to the condition being treated, to other medicines, or to something else.

Is this a list of the side effects of Terazosin?

No. It is a count of what was reported to FDA. The adverse reactions observed in clinical studies are printed on the FDA-approved label, which a pharmacist or clinician can go through with you.

How do I report an adverse event?

Consumers and health professionals can report to FDA through MedWatch (Form FDA 3500 online, or 1-800-FDA-1088), or to the manufacturer, which must pass reports on. See the guide on how to report.

Where this comes from. Counts are built from the openFDA Drug Adverse Event (FAERS) bulk export released 28 Sep 2026, which holds reports FDA received through 30 Jun 2026. Drug names are as reported, resolved to the brand or generic name on the FDA label where openFDA's harmonisation matched them; classes are the pharmacologic class (EPC) from the label and the National Drug Code Directory of 17 Sep 2026. A report counts here when it lists Terazosin as a suspect or interacting product; reports listing it only as a concomitant medication (7,107) are excluded. No report narrative, lot number, patient detail or reporter identity is published. See the methodology and sources; FDA's record is authoritative, and corrections are handled within five working days.

Drug data (FAERS) through 30 Jun 2026; device data (MAUDE) through 31 Aug 2026. Not medical advice.