ascorbic acid Side Effects
Also known as: Vitamin C
Analysis of 22,556 adverse event reports submitted to the FDA from 1999 to 2025.
Total Reports
22,556
Death-Related
2,511
11.1% of reports
Hospitalizations
9,031
40.0% of reports
Top Indication
Product Used For Unknown Indication
Most Reported Adverse Reactions
Who Reports Side Effects
Gender Distribution
Age Distribution
Reporting Trend by Year
Reactions in Death Reports
Top reactions reported in 2,511 reports where death was an outcome. These are voluntarily reported and do not establish causation.
| Reaction | Reports |
|---|---|
| DEATH | 556 |
| OFF LABEL USE | 435 |
| VOMITING | 420 |
| DYSPNOEA | 400 |
| FATIGUE | 392 |
| GENERAL PHYSICAL HEALTH DETERIORATION | 385 |
| NAUSEA | 375 |
| HYPERTENSION | 362 |
| CONDITION AGGRAVATED | 361 |
| DIARRHOEA | 353 |
| PAIN | 330 |
| PNEUMONIA | 330 |
| DRY MOUTH | 315 |
| PYREXIA | 314 |
| DRUG HYPERSENSITIVITY | 307 |
| HEADACHE | 300 |
| RHEUMATOID ARTHRITIS | 297 |
| ASTHENIA | 295 |
| RASH | 295 |
| CONFUSIONAL STATE | 294 |
Reactions in Hospitalization Reports
Top reactions in 9,031 reports where hospitalization was an outcome.
| Reaction | Reports |
|---|---|
| NAUSEA | 1,002 |
| DYSPNOEA | 994 |
| PAIN | 991 |
| FATIGUE | 978 |
| DIARRHOEA | 891 |
| VOMITING | 826 |
| ASTHENIA | 805 |
| PNEUMONIA | 798 |
| PYREXIA | 725 |
| OFF LABEL USE | 704 |
| FALL | 700 |
| DRUG INEFFECTIVE | 673 |
| HYPERTENSION | 657 |
| HEADACHE | 652 |
| DIZZINESS | 628 |
| ARTHRALGIA | 623 |
| CONDITION AGGRAVATED | 577 |
| CHEST PAIN | 547 |
| PAIN IN EXTREMITY | 540 |
| MALAISE | 539 |
Nearby — Related Medications
What the FAERS Data Reveals About ascorbic acid Side Effects
The FDA Adverse Event Reporting System (FAERS) contains 22,556 voluntary reports linked to ascorbic acid and its brand equivalents (Vitamin C), spanning 1999 through 2025. Of those, 2,511 (11.1%) listed death as an outcome and 9,031 (40.0%) 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, 63% were female and 37% male; age distribution skews toward 45-64, with 4,829 reports in that bracket. The single most reported reaction is fatigue with 2,275 submissions, followed by pain and nausea.
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.
Read our methodology — how this data is sourced, computed, and verified.