What the label lists and what reports show
Defibrotide side effects
Defibrotide's FDA label: “The most common adverse reactions (incidence ≥10% and independent of causality) with DEFITELIO treatment were hypotension, diarrhea, vomiting, nausea, and epistaxis.” FAERS holds 3,546 reports naming it through July 30, 2026; the reaction reported most often, leaving out the conditions it is used for, product-use terms and outcomes, is venoocclusive disease (564 reports).
- No generic listed
Check it at the source: the defibrotide FDA label on DailyMed (effective July 1, 2025, Jazz Pharmaceuticals, Inc.); the FDA FAERS public dashboard.
What does the label list?
From the label: adverse reactionsThe most common adverse reactions (incidence ≥10% and independent of causality) with DEFITELIO treatment were hypotension, diarrhea, vomiting, nausea, and epistaxis.
A table the label prints in its adverse reactions section without a title; its column headings name the groups compared
| Adverse Reaction a | Any grade | Grade 4-5 b |
|---|---|---|
| Hypotension | 65 (37%) | 12 (7%) |
| Diarrhea | 43 (24%) | 0 |
| Vomiting | 31 (18%) | 0 |
| Nausea | 28 (16%) | 0 |
| Epistaxis | 24 (14%) | 0 |
| Pulmonary alveolar hemorrhage | 15 (9%) | 12 (7%) |
| Gastrointestinal hemorrhage | 15 (9%) | 5 (3%) |
| Sepsis | 12 (7%) | 9 (5%) |
| Graft versus host disease | 11 (6%) | 7 (4%) |
| Lung infiltration | 10 (6%) | 5 (3%) |
| Pneumonia | 9 (5%) | 5 (3%) |
| Pulmonary hemorrhage | 7 (4%) | 4 (2%) |
| Infection | 6 (3%) | 4 (2%) |
| Hemorrhage intracranial | 5 (3%) | 4 (2%) |
| Hyperuricemia | 4 (2%) | 4 (2%) |
| Cerebral hemorrhage c | 3 (2%) | 3 (2%) |
Rows and numbers as the label prints them, under its own column headings (the first rows of a longer table where it runs on). A reaction in a trial table is not necessarily caused by the medicine, and trials differ from everyday use.
From the label: adverse reactions, continuedThe following adverse reactions are discussed in greater detail in other sections of the labeling: • Hemorrhage [see Warnings and Precautions (5.1) ] • Hypersensitivity Reactions [see Warnings and Precautions (5.2) ] The most common adverse reactions (incidence ≥10% and independent of causality) with DEFITELIO treatment were hypotension, diarrhea, vomiting, nausea, and epistaxis. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Jazz Pharmaceuticals, Inc. at 1-800-520-5568 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. The safety of DEFITELIO was determined in 176 adult and pediatric patients with hepatic VOD with pulmonary and/or renal dysfunction following HSCT who were treated with DEFITELIO 6.25 mg/kg every 6 hours [see Clinical Studies (14) ]. Patients were excluded from these trials if at time of study entry they had significant acute bleeding, active grades B-D graft-versus-host disease, or a requirement for multiple vasopressors to provide blood pressure support. …
Source: FDA drug label, Jazz Pharmaceuticals, Inc., effective July 1, 2025 (SPL set 2c3db989-d7ad-41ed-9ebf-698dcf6c24ec), via openFDA; the full label on DailyMed
What do FAERS reports show?
3,546 reports list defibrotide among the medicines taken, each a report of something that happened, not proof the medicine caused it; 1,730 are coded as a death and 762 as a hospital stay. Counts follow how widely a medicine is used and watched, and they are not a measure of how risky it is. Of the 19 reactions below, 10 are named by the same term (in US spelling) in the label's adverse reactions, warnings or patient leaflet; a reaction the label does not name may still be there under another word, and a report does not show that the medicine caused it.
Reports received each year
The 25 most reported reactions
Source: FDA Adverse Event Reporting System (FAERS) via openFDA, reports through July 30, 2026; reactions as MedDRA preferred terms
What next?
- Defibrotide: the full record
- label, generics, price, shortages, recalls
- Report a side effect to the FDA
- MedWatch
- Side effects hub
- the most reported medicines and reactions