Reported Reactions

Drugs

Product name as reported

Hydralazine: adverse event reports filed with FDA

4,297 reports list it as a suspect or interacting product, 2004–2026.

4,297
reports as suspect product
0% of all reports · about 195 a year
476
reports, 12 months to June 2026
373 in the 12 months before
89.3%
marked serious by the reporter
57.4% across all reports
15%
record death among outcomes, as reported
644 reports · not verified by FDA

4,297 adverse event reports received by FDA list the product name "Hydralazine" as reporters wrote it as a suspect or interacting product, from June 2004 to June 2026. A further 22,974 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, 476 reports listed it, up 28% from 373 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 195 reports a year and 0% of the 20,646,523 reports in the database. How many people take it is not in the data, so a count is not a rate of occurrence.

The reactions recorded most often are anti-neutrophil cytoplasmic antibody positive vasculitis (15.8%), drug ineffective (9.5%) and hypertension (6.5%). A report can list several reactions, so shares add to more than 100%; 817 different terms appear across these reports. Anti-neutrophil cytoplasmic antibody positive vasculitis is recorded in 15.8% of these reports, against 0% of all reports in the database.

89.3% of the reports are marked serious by the reporter; 15% record death among the outcomes and 48.7% record hospitalisation, as reported. 52.4% of the reports came from other health professionals, and the largest patient age group is 45 to 64 (21.5%). 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

03773Jul 2021: 26Aug 2021: 17Sep 2021: 34Oct 2021: 26Nov 2021: 15Dec 2021: 452022Jan 2022: 23Feb 2022: 38Mar 2022: 50Apr 2022: 28May 2022: 19Jun 2022: 15Jul 2022: 16Aug 2022: 10Sep 2022: 18Oct 2022: 35Nov 2022: 18Dec 2022: 282023Jan 2023: 28Feb 2023: 40Mar 2023: 25Apr 2023: 15May 2023: 41Jun 2023: 41Jul 2023: 42Aug 2023: 49Sep 2023: 24Oct 2023: 36Nov 2023: 21Dec 2023: 462024Jan 2024: 41Feb 2024: 13Mar 2024: 29Apr 2024: 35May 2024: 42Jun 2024: 42Jul 2024: 65Aug 2024: 28Sep 2024: 18Oct 2024: 25Nov 2024: 24Dec 2024: 682025Jan 2025: 37Feb 2025: 17Mar 2025: 19Apr 2025: 34May 2025: 14Jun 2025: 24Jul 2025: 47Aug 2025: 73Sep 2025: 43Oct 2025: 29Nov 2025: 21Dec 2025: 552026Jan 2026: 44Feb 2026: 48Mar 2026: 43Apr 2026: 33May 2026: 20Jun 2026: 20

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

02214422004: 420042005: 72006: 72007: 220072008: 12009: 392010: 4820102011: 232012: 322013: 13420132014: 1952015: 2202016: 22720162017: 1722018: 2632019: 32320192020: 4012021: 4422022: 29820222023: 4082024: 4302025: 41320252026: 208

2026 covers reports received through June 2026 only.

Reactions recorded in the reports

share of Hydralazine reports recording the termall reports in the database

  1. Anti-neutrophil cytoplasmic antibody positive vasculitis15.8%681
  2. Drug ineffectivethe medicine did not work as expected9.5%410
  3. Hypertensionhigh blood pressure6.5%278
  4. Acute kidney injurysudden loss of kidney function6.2%266
  5. Completed suicidedeath by suicide5.9%255
  6. Lupus-like syndromelupus-like symptoms4.8%208
  7. Foetal exposure during pregnancythe unborn baby was exposed to the medicine4.8%205
  8. Hypotensionlow blood pressure4.7%204
  9. Premature babya baby born early4.5%193
  10. Glomerulonephritis rapidly progressive3.9%168
  11. Dyspnoeashortness of breath3.8%164
  12. Drug hypersensitivityan allergic-type reaction to a medicine3.7%161
  13. Exposure during pregnancythe medicine was taken during pregnancy3.6%156
  14. Dizzinesslight-headedness or unsteadiness3.5%150
  15. Headachehead pain3.4%147
  16. Vasculitisinflammation of blood vessels3.4%145
  17. Maternal exposure during pregnancythe mother took the medicine during pregnancy3.3%142
  18. Toxicity to various agentspoisoning or toxic effect of one or more substances3.2%138
  19. Fatiguetiredness3.1%133
  20. Off label useused for a purpose or in a way not on the label2.9%124
  21. Gastrointestinal tract mucosal pigmentation2.8%120
  22. Nauseafeeling sick2.8%120
  23. Pulmonary renal syndrome2.8%119
  24. Oedema peripheralswelling of the legs, ankles or hands2.6%112
  25. Glomerulonephritis2.6%111
  26. Peripheral swellingswelling of the arms or legs2.5%107
  27. Rashskin rash2.5%106
  28. Blood pressure increaseda raised blood pressure reading2.4%104
  29. Contusiona bruise2.4%104

Top 30 of 817 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 share of all reports in the database; 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

Death15%644
Life-threatening9.1%390
Hospitalisation (initial or prolonged)48.7%2,093
Disability1.7%71
Congenital anomaly0.3%15
Other serious58.3%2,507
Not serious10.7%460

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 20,646,523 reports. 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 20.4%18
2 to 110.3%15
12 to 170.7%29
18 to 4411.4%492
45 to 6421.5%922
65 to 7418.5%794
75 and over21.4%920
Age not given25.8%1,107

Patient sex

Female51.4%2,207
Male31.9%1,370
Not given16.8%720

Who reported

Physician26.3%1,128
Pharmacist6.1%263
Other health professional52.4%2,251
Lawyer0.1%3
Consumer or non-health professional12.9%556
Not given2.2%96

Age and sex as stated in the report; the reporter's qualification is the primary source recorded by FDA. 79.8% of reports give the United States as the country of the event or reporter.

Reason for use recorded

Indication as recorded (MedDRA)ReportsShare
Hypertension1,63238%
Pre-eclampsia591.4%
Foetal exposure during pregnancy521.2%
Blood pressure abnormal461.1%
Blood pressure measurement370.9%
Cardiac failure350.8%

The indication field is filled in by the reporter and is often blank; shares are of all 4,297 reports.

Drugs most often listed in the same reports

Drug (any role in the report)ReportsShare of Hydralazine reports
Amlodipine84919.8%
Furosemide63714.8%
Metoprolol55312.9%
Carvedilol53512.5%
Labetalol4199.8%
Aspirin4009.3%
Nifedipine3869%
Lisinopril3397.9%
Clonidine3007%
Atorvastatin2626.1%

Other products listed in reports where Hydralazine 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

MeasureHydralazineAll reports
Reports as suspect product4,29720,646,523
Share of that pool—0%
Reports, latest 12 months4761,332,454
Marked serious89.3%57.4%
Death recorded among outcomes, per 1,000 reports15091
Hospitalisation recorded, per 1,000 reports487213
Consumer-filed share12.9%45.8%
Top term, share of reportsAnti-neutrophil cytoplasmic antibody positive vasculitis 15.8%0%

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."

Questions about Hydralazine reports

How many adverse event reports has FDA received for Hydralazine?

4,297 reports list Hydralazine as a suspect or interacting product in the openFDA FAERS release of 28 Sep 2026, covering reports received through June 2026. 476 of them arrived in the latest 12 months. Another 22,974 list it only as a concomitant medication.

What reactions are recorded in Hydralazine reports?

anti-neutrophil cytoplasmic antibody positive vasculitis (15.8%), drug ineffective (9.5%), hypertension (6.5%), acute kidney injury (6.2%) and completed suicide (5.9%). 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 Hydralazine was responsible.

How serious are the reports?

89.3% are marked serious by the reporter. Among the outcomes recorded, 15% of reports include death and 48.7% 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?

other health professional (52.4%), physician (26.3%) and consumer or non-health professional (12.9%). Most reports reach FDA through the manufacturer, which must forward reports it receives.

Are reports for Hydralazine rising?

476 reports in the 12 months to June 2026, up 28% from 373 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 Hydralazine 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 Hydralazine?

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 Hydralazine as a suspect or interacting product; reports listing it only as a concomitant medication (22,974) 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.