What the label lists and what reports show
Mitoxantrone side effects
Mitoxantrone's FDA label: “Clinical adverse events most frequently reported in the mitoxantrone injection group included amenorrhea (53% of female patients), alopecia (33% of patients), nausea (29% of patients), and asthenia (24% of patients).” FAERS holds 6,237 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 febrile neutropenia (765 reports).
- Generic listed
- Boxed warning
Check it at the source: the mitoxantrone FDA label on DailyMed (effective April 24, 2025, Meitheal Pharmaceuticals Inc.); the FDA FAERS public dashboard.
What does the patient leaflet say about side effects?
From the patient leaflet: What are the possible side effects of mitoXANTRONE?mitoXANTRONE may cause serious side effects, including: See “What is the most important information I should know about mitoXANTRONE?” The most common side effects of mitoXANTRONE include: blue-green colored urine for about 24 hours after receiving mitoXANTRONE. This color change is harmless. bluish coloring of the whites of your eyes for about 24 hours after receiving mitoXANTRONE. This color change is harmless. nausea constipation diarrhea stomach pain hair loss fever and chills due to infections cough and sore throat due to upper respiratory tract infection mouth sores due to mouth infection loss of your menstrual period Tell your doctor if you have any side effect that bothers you or that does not go away. These are not all the possible side effects of mitoXANTRONE. For more information, ask your doctor or pharmacist. Call your doctor for medical advice about side effects. […]
Source: FDA drug label, Meitheal Pharmaceuticals Inc., effective April 24, 2025 (SPL set 1634528a-30c5-4309-acc8-4c0293ae14ae), via openFDA; the full label on DailyMed
What does the label list?
From the label: adverse reactionsClinical adverse events most frequently reported in the mitoxantrone injection group included amenorrhea (53% of female patients), alopecia (33% of patients), nausea (29% of patients), and asthenia (24% of patients).
Table 7: Adverse Events of Any Intensity Occurring in ≥ 5% of Patients Trial CCI-NOV22
| Event | M + P (n = 80) % | P (n = 81) % |
|---|---|---|
| Nausea | 61 | 35 |
| Fatigue | 39 | 14 |
| Alopecia | 29 | 0 |
| Anorexia | 25 | 6 |
| Constipation | 16 | 14 |
| Dyspnea | 11 | 5 |
| Nail bed changes | 11 | 0 |
| Edema | 10 | 4 |
| Systemic infection | 10 | 7 |
| Mucositis | 10 | 0 |
| UTI | 9 | 4 |
| Emesis | 9 | 5 |
| Pain | 8 | 9 |
| Fever | 6 | 3 |
| Hemorrhage/bruise | 6 | 1 |
| Anemia | 5 | 3 |
| Cough | 5 | 0 |
| Decreased LVEF | 5 | 0 |
| Anxiety/depression | 5 | 3 |
| Dyspepsia | 5 | 6 |
| Skin infection | 5 | 3 |
| Blurred vision | 3 | 5 |
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, continuedMultiple Sclerosis Mitoxantrone injection has been administered to 149 patients with multiple sclerosis in two randomized clinical trials, including 21 patients who received mitoxantrone injection in combination with corticosteroids. In Study 1, the proportion of patients who discontinued treatment due to an adverse event was 9.7% (n = 6) in the 12 mg/m 2 mitoxantrone injection arm (leukopenia, depression, decreased LV function, bone pain and emesis, renal failure, and one discontinuation to prevent future complications from repeated urinary tract infections) compared to 3.1% (n = 2) in the placebo arm (hepatitis and myocardial infarction). The following clinical adverse experiences were significantly more frequent in the mitoxantrone injection groups: nausea, alopecia, urinary tract infection, and menstrual disorders, including amenorrhea. Table 4a summarizes clinical adverse events of all intensities occurring in ≥ 5% of patients in either dose group of mitoxantrone injection and that were numerically greater on drug than on placebo in Study 1. The majority of these events were of mild to moderate intensity, and nausea was the only adverse event that occurred with severe intensity in more than one patient (three patients [5%] in the 12 mg/m 2 group). Of note, alopecia consisted of mild hair thinning. …
Source: FDA drug label, Meitheal Pharmaceuticals Inc., effective April 24, 2025 (SPL set 1634528a-30c5-4309-acc8-4c0293ae14ae), via openFDA; the full label on DailyMed
What do FAERS reports show?
6,237 reports list mitoxantrone among the medicines taken, each a report of something that happened, not proof the medicine caused it; 1,662 are coded as a death and 2,215 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, 12 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?
- Mitoxantrone: 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