What the label lists and what reports show
Talazoparib side effects
Talazoparib's FDA label: “Most common adverse reactions (≥20%) as a single agent, including laboratory abnormalities, are: • Hemoglobin decreased, neutrophils decreased, lymphocytes decreased, platelets decreased, fatigue, glucose increased, aspartate aminotransferase increased …” FAERS holds 1,763 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 anaemia (273 reports).
- No generic listed
Check it at the source: the talazoparib FDA label on DailyMed (effective April 10, 2026, Pfizer Laboratories Div Pfizer 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 TALZENNA?TALZENNA may cause serious side effects, including: • See “ What is the most important information I should know about TALZENNA? ” The most common side effects of TALZENNA when taken alone include: • decreased red blood cell counts • decreased white blood cell counts • tiredness or weakness • decreased platelet counts • increased blood sugar levels • increased liver function tests • nausea • headache • decreased blood calcium levels • vomiting • hair loss • diarrhea • decreased appetite The most common side effects of TALZENNA when taken in combination with enzalutamide include: • decreased red blood cell counts • decreased white blood cell counts • tiredness or weakness • decreased platelet counts • decreased calcium in the blood • nausea • decreased appetite • decreased sodium in the blood • decreased phosphate in the blood • bone injuries • decreased magnesium in the blood • dizziness • increased bilirubin in the blood • decreased potassium in the blood • changes in your sense of taste TALZENNA may cause fertility problems in males. […]
Source: FDA drug label, Pfizer Laboratories Div Pfizer Inc, effective April 10, 2026 (SPL set c6fd147f-a77e-4a0b-9280-e82ecc41b4be), via openFDA; the full label on DailyMed
What does the label list?
From the label: adverse reactionsMost common adverse reactions (≥20%) as a single agent, including laboratory abnormalities, are: • Hemoglobin decreased, neutrophils decreased, lymphocytes decreased, platelets decreased, fatigue, glucose increased, aspartate aminotransferase increased, alkaline phosphatase increased, alanine aminotransferase increased, calcium decreased, nausea, headache, vomiting, alopecia, diarrhea, and decreased appetite.
Table 5. Adverse Reactions Graded according to NCI CTCAE 4.03. (≥20%) in Patients Receiving TALZENNA in EMBRACA
| Reaction | Grades 1-4 | Grade 3 | Grade 4 | Grades 1-4 | Grade 3 | Grade 4 |
|---|---|---|---|---|---|---|
| Fatigue Includes fatigue and asthenia. | 62 | 3 | 0 | 50 | 5 | 0 |
| Nausea | 49 | 0.3 | 0 | 47 | 2 | 0 |
| Vomiting | 25 | 2 | 0 | 23 | 2 | 0 |
| Diarrhea | 22 | 1 | 0 | 26 | 6 | 0 |
| Headache | 33 | 2 | 0 | 22 | 1 | 0 |
| Alopecia | 25 | 0 | 0 | 28 | 0 | 0 |
| Decreased appetite | 21 | 0.3 | 0 | 22 | 1 | 0 |
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 clinically significant adverse reactions are described elsewhere in the labeling: • Myelodysplastic Syndrome/Acute Myeloid Leukemia [see Warnings and Precautions (5.1) ] • Myelosuppression [see Warnings and Precautions (5.2) ] Most common adverse reactions (≥20%) as a single agent, including laboratory abnormalities, are: • Hemoglobin decreased, neutrophils decreased, lymphocytes decreased, platelets decreased, fatigue, glucose increased, aspartate aminotransferase increased, alkaline phosphatase increased, alanine aminotransferase increased, calcium decreased, nausea, headache, vomiting, alopecia, diarrhea, and decreased appetite. ( 6.1 ) Most common adverse reactions (≥10%) in combination with enzalutamide, including laboratory abnormalities, are: • Hemoglobin decreased, neutrophils decreased, lymphocytes decreased, fatigue, platelets decreased, calcium decreased, nausea, decreased appetite, sodium decreased, phosphate decreased, fractures, magnesium decreased, dizziness, bilirubin increased, potassium decreased, and dysgeusia. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Pfizer Inc. at 1-800-438-1985 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. …
Source: FDA drug label, Pfizer Laboratories Div Pfizer Inc, effective April 10, 2026 (SPL set c6fd147f-a77e-4a0b-9280-e82ecc41b4be), via openFDA; the full label on DailyMed
What do FAERS reports show?
1,763 reports list talazoparib among the medicines taken, each a report of something that happened, not proof the medicine caused it; 328 are coded as a death and 614 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 22 reactions below, 14 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?
- Talazoparib: 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