What the label lists and what reports show
Fludarabine side effects
Fludarabine's FDA label: “The most common adverse events include myelosuppression (neutropenia, thrombocytopenia and anemia), fever and chills, infection, and nausea and vomiting.” FAERS holds 39,093 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 pyrexia (2,930 reports).
- Generic listed
- Boxed warning
Check it at the source: the fludarabine FDA label on DailyMed (effective October 14, 2024, Fresenius Kabi USA, LLC); the FDA FAERS public dashboard.
What does the label list?
From the label: adverse reactionsThe most common adverse events include myelosuppression (neutropenia, thrombocytopenia and anemia), fever and chills, infection, and nausea and vomiting.
TABLE 1: PERCENT OF CLL PATIENTS REPORTING NON-HEMATOLOGIC ADVERSE REACTIONS
This table is printed in the Fludarabine Phosphate label published by Sagent Pharmaceuticals of July 22, 2021; the label quoted above does not print one.
| ADVERSE REACTIONS | MDAH (N=101) | SWOG (N=32) |
|---|---|---|
| ANY ADVERSE REACTION | 88% | 91% |
| BODY AS A WHOLE | 72 | 84 |
| FEVER | 60 | 69 |
| CHILLS | 11 | 19 |
| FATIGUE | 10 | 38 |
| INFECTION | 33 | 44 |
| PAIN | 20 | 22 |
| MALAISE | 8 | 6 |
| DIAPHORESIS | 1 | 13 |
| ALOPECIA | 0 | 3 |
| ANAPHYLAXIS | 1 | 0 |
| HEMORRHAGE | 1 | 0 |
| HYPERGLYCEMIA | 1 | 6 |
| DEHYDRATION | 1 | 0 |
| NEUROLOGICAL | 21 | 69 |
| WEAKNESS | 9 | 65 |
| PARESTHESIA | 4 | 12 |
| HEADACHE | 3 | 0 |
| VISUAL DISTURBANCE | 3 | 15 |
| HEARING LOSS | 2 | 6 |
| SLEEP DISORDER | 1 | 3 |
| DEPRESSION | 1 | 0 |
| CEREBELLAR SYNDROME | 1 | 0 |
| IMPAIRED MENTATION | 1 | 0 |
| PULMONARY | 35 | 69 |
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 most common adverse events include myelosuppression (neutropenia, thrombocytopenia and anemia), fever and chills, infection, and nausea and vomiting. Other commonly reported events include malaise, fatigue, anorexia, and weakness. Serious opportunistic infections have occurred in CLL patients treated with fludarabine. The most frequently reported adverse events and those reactions which are more clearly related to the drug are arranged below according to body system. Hematopoietic Systems Hematologic events (neutropenia, thrombocytopenia, and/or anemia) were reported in the majority of CLL patients treated with fludarabine. During fludarabine treatment of 133 patients with CLL, the absolute neutrophil count decreased to less than 500/mm 3 in 59% of patients, hemoglobin decreased from pretreatment values by at least 2 grams percent in 60%, and platelet count decreased from pretreatment values by at least 50% in 55%. Myelosuppression may be severe, cumulative, and may affect multiple cell lines. Bone marrow fibrosis occurred in one CLL patient treated with fludarabine. Several instances of trilineage bone marrow hypoplasia or aplasia resulting in pancytopenia, sometimes resulting in death, have been reported in postmarketing surveillance. The duration of clinically significant cytopenia in the reported cases has ranged from approximately 2 months to approximately 1 year. …
Source: FDA drug label, Fresenius Kabi USA, LLC, effective October 14, 2024 (SPL set cf5255cc-91fd-4132-973b-764dba142eae), via openFDA; the full label on DailyMed
What do FAERS reports show?
39,093 reports list fludarabine among the medicines taken, each a report of something that happened, not proof the medicine caused it; 11,956 are coded as a death and 11,276 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 20 reactions below, 9 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?
- Fludarabine: 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