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Drug side effects

hydralazine Side Effects

The reactions most often reported to the FDA for hydralazine (also sold as Apresoline), with demographics, serious outcomes, and reporting trends.

Data updated 2026-05-15

28,498
FAERS reports

Data from the FDA Adverse Event Reporting System (FAERS), 1995 to 2025. A FAERS report records a temporal association, not proof of cause. See our methodology for how figures are compiled and de-duplicated.

The most commonly reported side effects of hydralazine come from 28,498 reports to the FDA, broken down here by frequency, patient demographics, and serious outcomes.

This page analyzes 28,498 reports to the FDA Adverse Event Reporting System (FAERS) for hydralazine (Apresoline): the reactions reported most often, who reported them, serious outcomes such as hospitalization, and year-over-year trends. A FAERS report does not prove the drug caused the effect, and report volume tracks how widely a drug is used, not how likely an effect is for any one person. Educational information, not medical advice.

Total Reports

28,498

Reports Mentioning Death

3,510

12.3% of reports — not proof the medicine caused the death

Hospitalizations

12,190

42.8% of reports

Top Indication

Product Used For Unknown Indication

Most Reported Adverse Reactions

CHRONIC KIDNEY DISEASE
2,819
ACUTE KIDNEY INJURY
2,616
RENAL FAILURE
2,097
END STAGE RENAL DISEASE
1,585
FATIGUE
1,542
DYSPNOEA
1,535
DIARRHOEA
1,407
NAUSEA
1,337
DEATH
1,316
HYPERTENSION
1,312
ANTI-NEUTROPHIL CYTOPLASMIC ANTIBODY POSITIVE VASCULITIS
1,005
ASTHENIA
973
DIZZINESS
958
HEADACHE
943
CARDIAC FAILURE CONGESTIVE
884
PAIN
872
PNEUMONIA
859
BLOOD PRESSURE INCREASED
827

Who Reports Side Effects

Gender Distribution

Female 14,054 (54%)
Male 11,762 (45%)
Unknown 50

Age Distribution

0-17 325 (2%)
18-44 1,742 (9%)
45-64 6,121 (31%)
65-74 5,477 (28%)
75+ 5,829 (30%)

Reporting Trend by Year

1995 2025

Reactions in Death Reports

Top reactions reported in 3,510 reports where death was an outcome. These are voluntarily reported and do not establish causation.

Reaction Reports
DEATH 1,309
CHRONIC KIDNEY DISEASE 530
ACUTE KIDNEY INJURY 449
RENAL FAILURE 409
END STAGE RENAL DISEASE 403
COMPLETED SUICIDE 255
CARDIAC ARREST 182
CARDIAC FAILURE CONGESTIVE 160
NEPHROGENIC ANAEMIA 157
PNEUMONIA 144
DYSPNOEA 129
SEPSIS 126
RESPIRATORY FAILURE 121
TOXICITY TO VARIOUS AGENTS 115
ANAEMIA 102
HYPERTENSION 99
RENAL INJURY 98
ATRIAL FIBRILLATION 94
CEREBROVASCULAR ACCIDENT 93
ASTHENIA 92

Reactions in Hospitalization Reports

Top reactions in 12,190 reports where hospitalization was an outcome.

Reaction Reports
ACUTE KIDNEY INJURY 1,201
DYSPNOEA 895
RENAL FAILURE 836
HYPERTENSION 767
CHRONIC KIDNEY DISEASE 753
PNEUMONIA 708
CARDIAC FAILURE CONGESTIVE 704
ANTI-NEUTROPHIL CYTOPLASMIC ANTIBODY POSITIVE VASCULITIS 671
FATIGUE 599
NAUSEA 595
FALL 553
DIARRHOEA 541
ASTHENIA 537
END STAGE RENAL DISEASE 480
ANAEMIA 476
VOMITING 446
HYPOTENSION 444
DIZZINESS 433

Compare hydralazine vs acebutolol →

What the FAERS Data Reveals About hydralazine Side Effects

The FDA Adverse Event Reporting System (FAERS) contains 28,498 voluntary reports linked to hydralazine and its brand equivalents (Apresoline), spanning 1995 through 2025. Of those, 3,510 (12.3%) listed death as an outcome and 12,190 (42.8%) involved hospitalization. The most common indication reported alongside adverse events was Product Used For Unknown Indication.

Demographic breakdowns help contextualize who is being exposed to the drug. Of reports with known sex, 54% were female and 45% male; age distribution skews toward 45-64, with 6,121 reports in that bracket. The single most reported reaction is chronic kidney disease with 2,819 submissions, followed by acute kidney injury and renal failure.

How to read these numbers

FAERS is a signal-detection tool, not a scorecard. Reports are voluntary, and a single case may list multiple suspect drugs, so numbers above should not be read as incidence rates or per-patient risk. Widely prescribed drugs naturally accumulate more reports than niche therapies even when individual risk is low. These aggregates are useful for spotting patterns that merit further pharmacovigilance, not for choosing between medications. This page is for educational reference only and is not medical advice, speak with a licensed clinician about any side-effect concerns.