Deferiprone side effects: what 3,004 FDA adverse event reports show
Drug class
Iron Chelator
Brand names
Ferriprox
Who reports
3,004 reports · 71% serious · 371 with death outcome · 57% female
Used for
FERRIPROX Tablets are indicated for the treatment of transfusional iron overload in adult and pediatric patients 8 years of age and older with thalassemia syndromes, sickle cell disease or other anemias. Limitation s of Use • Safety and effectiveness have not been established for the treatment of transfusional iron overload in patients with myelodysplastic syndrome or in patients with Diamond Blackfan anemia.
What it is
FERRIPROX Tablets (deferiprone) contain 1,000 mg deferiprone (3-hydroxy-1,2-dimethylpyridin-4-one), a synthetic, orally active, iron-chelating agent.
Boxed warning
AGRANULOCYTOSIS AND NEUTROPENIA • FERRIPROX can cause agranulocytosis that can lead to serious infections and death. Neutropenia may precede the development of agranulocytosis. [see Warnings and Precautions ( 5.1 )] • Measure the absolute neutrophil count (ANC) before starting FERRIPROX therapy and monitor regularly while on therapy.
Causality screen of the 25 strongest signals
What the badges mean
- Labeled — boxed warning The term (or its clinical synonym) appears in the FDA boxed warning: causality is regulator-recognised and considered serious.
- Labeled adverse reaction The exact term appears in the label's warnings or adverse-reactions sections: a known, expected effect. The FAERS signal confirms the label rather than discovering anything.
- Labeled (related wording) The label describes this effect under different wording (e.g. 'neutropenia' for 'neutrophil count decreased'). Treated as known.
- Reporting / coding artifact An administrative, monitoring or exposure term (product issue, off-label use, 'test normal', overdose...). Not a biological reaction; a high PRR here reflects how reports are coded.
- Lab value / disease marker A laboratory result, investigation or disease-activity marker (antibody positive, CRP abnormal, swollen joint count) not described in the label. These usually mirror the monitored disease or testing protocol rather than a drug effect; not screened further.
- Not in label — unassessed Not found in the label text, not an artifact pattern. This is a genuine candidate for a formal causality assessment (Bradford Hill / WHO-UMC); it has NOT had one here.
Strongest disproportionality signals
Flagged terms (PRR ≥ 2, χ² ≥ 4, n ≥ 10), ranked by PRR; infinite PRRs (no comparator reports) excluded. The EBGM column is a second, shrinkage-based estimate (MGPS) with its 5th percentile EB05 and the BCPNN IC025; a pair flagged by PRR alone is marked PRR-only and should be read as fragile. The strata column recomputes the PRR on serious reports only and flags pairs whose reports are unusually skewed by sex or come mostly from consumers rather than clinicians. 36 further terms are in the interactive explorer. Reaction links open the term's cross-drug page.
| Reaction | Reports | PRR 95% CI · ROR · χ²/p | EBGM EB05 · IC025 | Label screen | Serious-only & strata | Trial cross-check |
|---|---|---|---|---|---|---|
| Sickle cell anaemia with crisis | 191 | 85.4 74.4–98.1ROR 91.1 · χ² 15,668 / p <1e-300 | 83.7 EB05 74.2 · IC025 +5.9 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 95.4 | no trial data cached |
| Agranulocytosis (severe loss of white cells) | 158 | 60.2 51.7–70.1ROR 63.5 · χ² 9,063 / p <1e-300 | 59.3 EB05 51.9 · IC025 +5.4 3/3 methods agree | Labeled — boxed warning exact term | serious PRR 48.4 | no trial data cached |
| Prescribed overdose | 95 | 34.4 28.2–42.0ROR 35.5 · χ² 3,038 / p <1e-300 | 34.1 EB05 28.7 · IC025 +4.5 3/3 methods agree | Not in label — unassessed | serious PRR 28.6 · 76% consumer | no trial data cached |
| Chromaturia | 58 | 18.0 13.9–23.2ROR 18.3 · χ² 911 / p 2e-200 | 17.8 EB05 14.3 · IC025 +3.5 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 6.0 · 86% consumer | no trial data cached |
| Ill-defined disorder | 135 | 15.5 13.2–18.3ROR 16.2 · χ² 1,822 / p <1e-300 | 15.5 EB05 13.4 · IC025 +3.6 3/3 methods agree | Not in label — unassessed | serious PRR 18.8 · 73% consumer | no trial data cached |
| Neuroleptic malignant syndrome | 19 | 11.2 7.1–17.5ROR 11.2 · χ² 166 / p 3e-38 | 10.1 EB05 6.5 · IC025 +2.4 3/3 methods agree | Not in label — unassessed | serious PRR 9.1 | no trial data cached |
| Treatment noncompliance | 78 | 10.0 8.1–12.5ROR 10.3 · χ² 626 / p 2e-138 | 9.8 EB05 8.0 · IC025 +2.9 3/3 methods agree | Reporting / coding artifact | serious PRR 8.2 | no trial data cached |
| Off label use (used outside approved label) | 1,007 | 8.1 7.7–8.5ROR 11.7 · χ² 6,531 / p <1e-300 | 8.1 EB05 7.7 · IC025 +2.9 3/3 methods agree | Reporting / coding artifact | serious PRR 7.3 · 81% consumer | no trial data cached |
| Hepatomegaly | 10 | 7.1 3.8–13.1ROR 7.1 · χ² 46 / p 5e-12 | 5.6 EB05 3.2 · IC025 +1.4 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 6.3 | no trial data cached |
| Neutrophil count decreased | 39 | 6.7 4.9–9.2ROR 6.8 · χ² 185 / p 2e-42 | 6.3 EB05 4.8 · IC025 +2.1 3/3 methods agree | Labeled — boxed warning synonym match | serious PRR 4.7 | no trial data cached |
| Neutropenia (low neutrophils (infection-fighting cells)) | 122 | 6.3 5.3–7.5ROR 6.5 · χ² 541 / p 7e-120 | 6.2 EB05 5.3 · IC025 +2.3 3/3 methods agree | Labeled — boxed warning exact term | serious PRR 5.3 | no trial data cached |
| Hepatic cirrhosis | 16 | 6.0 3.7–9.7ROR 6.0 · χ² 61 / p 2e-15 | 5.2 EB05 3.4 · IC025 +1.5 3/3 methods agree | Not in label — unassessed | serious PRR 4.9 | no trial data cached |
| Haemoglobin decreased | 88 | 6.0 4.9–7.3ROR 6.1 · χ² 361 / p 9e-81 | 5.8 EB05 4.8 · IC025 +2.2 3/3 methods agree | Labeled — boxed warning synonym match | serious PRR 4.6 | no trial data cached |
| Product use complaint | 13 | 5.9 3.4–10.1ROR 5.9 · χ² 48 / p 3e-12 | 4.9 EB05 3.1 · IC025 +1.4 3/3 methods agree | Reporting / coding artifact | serious n=6 | no trial data cached |
| Hepatic enzyme increased | 51 | 5.2 4.0–6.9ROR 5.3 · χ² 171 / p 2e-39 | 5.0 EB05 4.0 · IC025 +1.9 3/3 methods agree | Labeled — boxed warning synonym match | serious PRR 3.5 | no trial data cached |
| Liver function test increased | 16 | 5.2 3.2–8.5ROR 5.3 · χ² 51 / p 5e-13 | 4.6 EB05 3.0 · IC025 +1.4 3/3 methods agree | Not in label — unassessed | serious PRR 4.6 | no trial data cached |
| Nephrolithiasis (kidney stones) | 34 | 5.2 3.7–7.3ROR 5.2 · χ² 111 / p 3e-26 | 4.9 EB05 3.6 · IC025 +1.7 3/3 methods agree | Not in label — unassessed | serious PRR 4.7 · ♀ 16% (drug 57%) | no trial data cached |
| White blood cell count decreased | 72 | 4.6 3.7–5.8ROR 4.7 · χ² 202 / p 3e-46 | 4.5 EB05 3.7 · IC025 +1.8 3/3 methods agree | Labeled (related wording) related wording | serious PRR 4.5 | no trial data cached |
| Device related infection | 10 | 4.5 2.4–8.4ROR 4.5 · χ² 24 / p 5e-7 | 3.8 EB05 2.3 · IC025 +0.9 3/3 methods agree | Reporting / coding artifact | serious PRR 3.8 | no trial data cached |
| White blood cell count increased | 24 | 4.4 2.9–6.5ROR 4.4 · χ² 59 / p 9e-15 | 4.0 EB05 2.9 · IC025 +1.3 3/3 methods agree | Lab value / disease marker | serious PRR 2.8 | no trial data cached |
| Pulmonary hypertension | 13 | 4.3 2.5–7.5ROR 4.4 · χ² 30 / p 2e-8 | 3.8 EB05 2.4 · IC025 +1.0 3/3 methods agree | Labeled (related wording) related wording | serious PRR 3.6 | no trial data cached |
| Abdominal discomfort | 88 | 3.7 3.0–4.5ROR 3.8 · χ² 170 / p 4e-39 | 3.6 EB05 3.0 · IC025 +1.5 3/3 methods agree | Labeled (related wording) related wording | serious PRR 1.7 · 74% consumer | no trial data cached |
| Viral infection | 17 | 3.6 2.2–5.7ROR 3.6 · χ² 29 / p 4e-8 | 3.3 EB05 2.2 · IC025 +0.9 3/3 methods agree | Labeled (related wording) related wording | serious PRR 2.9 | no trial data cached |
| Cardiac failure (heart failure) | 34 | 3.0 2.1–4.1ROR 3.0 · χ² 42 / p 4e-11 | 2.9 EB05 2.2 · IC025 +1.0 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 2.4 | no trial data cached |
| Leukopenia (low white blood cells) | 20 | 2.8 1.8–4.3ROR 2.8 · χ² 21 / p 2e-6 | 2.7 EB05 1.8 · IC025 +0.7 | Not in label — unassessed | serious PRR 2.4 | no trial data cached |
Trial evidence (ClinicalTrials.gov)
Most frequently reported reactions
By raw co-report count, regardless of disproportionality. Common terms here are often the illness itself or generic outcomes.
| Reaction | Reports | PRR 95% CI · ROR · χ²/p | EBGM EB05 · IC025 | Label screen | Serious-only & strata | Trial cross-check |
|---|---|---|---|---|---|---|
| Off label use (used outside approved label) | 1,007 | 8.1 7.7–8.5ROR 11.7 · χ² 6,531 / p <1e-300 | 8.1 EB05 7.7 · IC025 +2.9 3/3 methods agree | Reporting / coding artifact | serious PRR 7.3 · 81% consumer | no trial data cached |
| Death | 234 | 1.9 1.7–2.1ROR 2.0 · χ² 103 / p 2e-24 | 1.9 EB05 1.7 · IC025 +0.7 | Outcome field, not a reaction boxed warning mentions mortality | serious PRR 1.5 | no trial data cached |
| Sickle cell anaemia with crisis | 191 | 85.4 74.4–98.1ROR 91.1 · χ² 15,668 / p <1e-300 | 83.7 EB05 74.2 · IC025 +5.9 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 95.4 | no trial data cached |
| Agranulocytosis (severe loss of white cells) | 158 | 60.2 51.7–70.1ROR 63.5 · χ² 9,063 / p <1e-300 | 59.3 EB05 51.9 · IC025 +5.4 3/3 methods agree | Labeled — boxed warning exact term | serious PRR 48.4 | no trial data cached |
| Ill-defined disorder | 135 | 15.5 13.2–18.3ROR 16.2 · χ² 1,822 / p <1e-300 | 15.5 EB05 13.4 · IC025 +3.6 3/3 methods agree | Not in label — unassessed | serious PRR 18.8 · 73% consumer | no trial data cached |
| Neutropenia (low neutrophils (infection-fighting cells)) | 122 | 6.3 5.3–7.5ROR 6.5 · χ² 541 / p 7e-120 | 6.2 EB05 5.3 · IC025 +2.3 3/3 methods agree | Labeled — boxed warning exact term | serious PRR 5.3 | no trial data cached |
| Prescribed overdose | 95 | 34.4 28.2–42.0ROR 35.5 · χ² 3,038 / p <1e-300 | 34.1 EB05 28.7 · IC025 +4.5 3/3 methods agree | Not in label — unassessed | serious PRR 28.6 · 76% consumer | no trial data cached |
| Abdominal discomfort | 88 | 3.7 3.0–4.5ROR 3.8 · χ² 170 / p 4e-39 | 3.6 EB05 3.0 · IC025 +1.5 3/3 methods agree | Labeled (related wording) related wording | serious PRR 1.7 · 74% consumer | no trial data cached |
| Haemoglobin decreased | 88 | 6.0 4.9–7.3ROR 6.1 · χ² 361 / p 9e-81 | 5.8 EB05 4.8 · IC025 +2.2 3/3 methods agree | Labeled — boxed warning synonym match | serious PRR 4.6 | no trial data cached |
| Treatment noncompliance | 78 | 10.0 8.1–12.5ROR 10.3 · χ² 626 / p 2e-138 | 9.8 EB05 8.0 · IC025 +2.9 3/3 methods agree | Reporting / coding artifact | serious PRR 8.2 | no trial data cached |
| White blood cell count decreased | 72 | 4.6 3.7–5.8ROR 4.7 · χ² 202 / p 3e-46 | 4.5 EB05 3.7 · IC025 +1.8 3/3 methods agree | Labeled (related wording) related wording | serious PRR 4.5 | no trial data cached |
| Chromaturia | 58 | 18.0 13.9–23.2ROR 18.3 · χ² 911 / p 2e-200 | 17.8 EB05 14.3 · IC025 +3.5 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 6.0 · 86% consumer | no trial data cached |
| Hepatic enzyme increased | 51 | 5.2 4.0–6.9ROR 5.3 · χ² 171 / p 2e-39 | 5.0 EB05 4.0 · IC025 +1.9 3/3 methods agree | Labeled — boxed warning synonym match | serious PRR 3.5 | no trial data cached |
| Neutrophil count decreased | 39 | 6.7 4.9–9.2ROR 6.8 · χ² 185 / p 2e-42 | 6.3 EB05 4.8 · IC025 +2.1 3/3 methods agree | Labeled — boxed warning synonym match | serious PRR 4.7 | no trial data cached |
| Cardiac failure (heart failure) | 34 | 3.0 2.1–4.1ROR 3.0 · χ² 42 / p 4e-11 | 2.9 EB05 2.2 · IC025 +1.0 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 2.4 | no trial data cached |
Unlabeled candidate signals
These flagged terms were not found in the FDA label text and do not match an artifact pattern. They are the pairs that would merit a structured assessment (temporality, dose-response, biological plausibility, consistency across databases, trial or cohort evidence). The screen has not done that; string-matching misses label wording, and a strong PRR can still be stimulated reporting, co-medication, or the disease itself.
- Prescribed overdose — n=95, PRR 34.4
- Ill-defined disorder — n=135, PRR 15.5
- Nephrolithiasis — n=34, PRR 5.2
- Leukopenia — n=20, PRR 2.8
✓ A hand-written Bradford Hill causality assessment exists for this drug: Deferiprone ↔ Agranulocytosis.
Want to assess one of these properly? The runbook describes the Bradford Hill / trial-evidence workflow used on the assessment page, and handoff_top1000_signals.csv lists the strongest unassessed pairs across all drugs.
Common questions
What are the most reported side effects of Deferiprone?
In FDA FAERS, the most frequently co-reported reaction terms for Deferiprone are sickle cell anaemia with crisis, agranulocytosis, ill-defined disorder, neutropenia, prescribed overdose, abdominal discomfort. These are report counts, not rates: FAERS has no denominator, reporting is voluntary and uneven, and a term can be reported because of the illness being treated rather than the drug.
Does Deferiprone have an FDA boxed warning?
Yes. The current FDA label carries a boxed warning: AGRANULOCYTOSIS AND NEUTROPENIA • FERRIPROX can cause agranulocytosis that can lead to serious infections and death. Neutropenia may precede the development of agranulocytosis. [see Warnings and Precautions ( 5.1 )] • Measure the absolute neutrophil count (ANC) before starting FERRIPROX therapy and monitor regularly while on therapy.
Do FAERS signals prove that Deferiprone causes these side effects?
No. A disproportionality signal (PRR, ROR) means a reaction is reported more often with this drug than with others in the database. That can reflect a real effect, but also the disease being treated, stimulated reporting after news or litigation, co-medications, or how reports are coded. Causality needs temporality, dose-response, biological plausibility, consistency across data sources and, ideally, trial or cohort evidence. This page screens each term against the FDA label and ClinicalTrials.gov results; it does not establish causation.
Sources & methods
- FDA label via openFDA (set ID 946718ff-df43-1baa-74d1-e5bcfbe8ad86, effective 20260128; matched on
openfda.generic_name.exact:"DEFERIPRONE") - Bayesian shrinkage measures computed offline over all 1,317,300 cached pairs: BCPNN information component (IC, with Norén closed-form IC025) and MGPS empirical-Bayes geometric mean (EBGM, EB05) with a two-component gamma prior fitted by maximum marginal likelihood (α₁=0.57, β₁=0.02, α₂=1.42, β₂=0.70, w=0.17); unstratified
- FAERS pair statistics from the OpenPV build of 2026-09-14 (openFDA
count=aggregation, fieldpatient.drug.openfda.generic_name.exact, 61 reaction terms, min 3 co-reports); PRR/ROR with 95% CI, chi-square with Yates correction - Serious-only and stratified counts (serious:1, patient.patientsex, primarysource.qualification) from openFDA count queries; serious-only PRR uses the drug serious report total and the term global serious total (N_serious=11,882,979); strata shown only when n ≥ 20
- Seriousness and sex counts from openFDA
count=serious,patient.patientsex,seriousnessdeath
Page generated 2026-10-08. Label and PubChem text are retrieved automatically and may lag the current label; always check the current prescribing information. OpenPV is a beta research tool of the Open Source Medicine Foundation.