propylthiouracil Side Effects
Also known as: PTU
Analysis of 1,982 adverse event reports submitted to the FDA from 2004 to 2025.
Total Reports
1,982
Death-Related
170
8.6% of reports
Hospitalizations
907
45.8% of reports
Top Indication
Hyperthyroidism
Most Reported Adverse Reactions
Who Reports Side Effects
Gender Distribution
Age Distribution
Reporting Trend by Year
Reactions in Death Reports
Top reactions reported in 170 reports where death was an outcome. These are voluntarily reported and do not establish causation.
| Reaction | Reports |
|---|---|
| CARDIAC ARREST | 23 |
| DEATH | 21 |
| MULTIPLE ORGAN DYSFUNCTION SYNDROME | 19 |
| ACUTE KIDNEY INJURY | 14 |
| RENAL FAILURE | 13 |
| CARDIAC FAILURE CONGESTIVE | 11 |
| ACUTE HEPATIC FAILURE | 10 |
| PNEUMONIA | 10 |
| CIRCULATORY COLLAPSE | 9 |
| DRUG REACTION WITH EOSINOPHILIA AND SYSTEMIC SYMPTOMS | 9 |
| HYPERTHYROIDISM | 9 |
| HYPOTENSION | 9 |
| NAUSEA | 9 |
| SEPTIC SHOCK | 9 |
| CARDIOGENIC SHOCK | 8 |
| CHRONIC KIDNEY DISEASE | 8 |
| DRUG INEFFECTIVE | 8 |
| END STAGE RENAL DISEASE | 8 |
| THYROTOXIC CRISIS | 8 |
| CARDIO-RESPIRATORY ARREST | 7 |
Reactions in Hospitalization Reports
Top reactions in 907 reports where hospitalization was an outcome.
| Reaction | Reports |
|---|---|
| DRUG INEFFECTIVE | 111 |
| HYPERTHYROIDISM | 82 |
| OFF LABEL USE | 60 |
| HYPOTENSION | 49 |
| NAUSEA | 45 |
| AGRANULOCYTOSIS | 42 |
| PYREXIA | 41 |
| VOMITING | 36 |
| ACUTE KIDNEY INJURY | 35 |
| ANTI-NEUTROPHIL CYTOPLASMIC ANTIBODY POSITIVE VASCULITIS | 35 |
| THYROTOXIC CRISIS | 35 |
| ACUTE HEPATIC FAILURE | 33 |
| CARDIOGENIC SHOCK | 31 |
| CONDITION AGGRAVATED | 30 |
| PNEUMONIA | 30 |
| CARDIAC ARREST | 29 |
| DIARRHOEA | 28 |
| ANAEMIA | 27 |
| FATIGUE | 27 |
| FOETAL EXPOSURE DURING PREGNANCY | 26 |
Nearby — Related Medications
What the FAERS Data Reveals About propylthiouracil Side Effects
The FDA Adverse Event Reporting System (FAERS) contains 1,982 voluntary reports linked to propylthiouracil and its brand equivalents (PTU), spanning 2004 through 2025. Of those, 170 (8.6%) listed death as an outcome and 907 (45.8%) involved hospitalization. The most common indication reported alongside adverse events was Hyperthyroidism.
Demographic breakdowns help contextualize who is being exposed to the drug. Of reports with known sex, 73% were female and 26% male; age distribution skews toward 18-44, with 577 reports in that bracket. The single most reported reaction is drug ineffective with 189 submissions, followed by off label use and hyperthyroidism.
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.