What the label lists and what reports show
Dostarlimab side effects
Dostarlimab's FDA label: “Most common adverse reactions (≥20%), including laboratory abnormalities, with JEMPERLI in combination with carboplatin and paclitaxel in patients with EC are decreased hemoglobin, increased creatinine, peripheral neuropathy, decreased white blood cell count …” FAERS holds 2,264 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 malignant neoplasm progression (229 reports).
- No generic listed
Check it at the source: the dostarlimab FDA label on DailyMed (effective September 2, 2025); 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 JEMPERLI?JEMPERLI can cause serious side effects. • See “What is the most important information I should know about JEMPERLI?” The most common side effects of JEMPERLI when given with carboplatin and paclitaxel in people with EC include: • nerve problems in your arms, hands, legs, and feet • tiredness • nausea • hair loss • joint pain • rash • constipation • diarrhea • stomach-area (abdomen) pain • shortness of breath • decreased appetite • urinary tract infections • vomiting The most common side effects of JEMPERLI in people with dMMR solid tumors (including EC) when used alone include: • tiredness and weakness • low red blood cell count (anemia) • diarrhea • nausea • constipation • vomiting These are not all of the possible side effects of JEMPERLI. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
Source: FDA drug label, GlaxoSmithKline LLC, effective September 2, 2025 (SPL set 095eab9f-545a-4f12-bfb7-19477fb901a5), via openFDA; the full label on DailyMed
What does the label list?
From the label: adverse reactionsMost common adverse reactions (≥20%), including laboratory abnormalities, with JEMPERLI in combination with carboplatin and paclitaxel in patients with EC are decreased hemoglobin, increased creatinine, peripheral neuropathy, decreased white blood cell count, fatigue, nausea, alopecia, decreased platelets, increased glucose, decreased lymphocytes, decreased magnesium, decreased neutrophils, increased aspartate aminotransferase (AST), arthralgia, rash, constipation, diarrhea, increased alanine aminotransferase (ALT) […]
Table 3. Adverse Reactions (≥20%) in Patients with Endometrial Cancer Who Received JEMPERLI with Carboplatin and Paclitaxel in RUBY
| Reaction | All Grades % | Grade 3 or 4 % | All Grades % | Grade 3 or 4 % |
|---|---|---|---|---|
| Peripheral neuropathy a | 64 | 4.1 | 61 | 2.0 |
| Fatigue b | 56 | 3.3 | 63 | 5 |
| Nausea | 54 | 2.9 | 46 | 1.6 |
| Constipation | 35 | 0.4 | 36 | 0 |
| Diarrhea | 32 | 1.7 | 29 | 0.8 |
| Abdominal pain c | 24 | 2.5 | 29 | 2 |
| Vomiting | 20 | 1.7 | 20 | 1.6 |
| Alopecia | 54 | 0 | 50 | 1.2 |
| Rash d | 37 | 7 | 18 | 1.2 |
| Arthralgia | 37 | 1.2 | 35 | 0.4 |
| Dyspnea e | 23 | 1.7 | 26 | 0.8 |
| Decreased appetite | 22 | 2.1 | 18 | 0.4 |
| Urinary tract infection f | 21 | 3.3 | 18 | 1.6 |
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: • Severe and fatal immune-mediated adverse reactions [see Warnings and Precautions ( 5.1 )] • Infusion-related reactions [see Warnings and Precautions ( 5.2 )] • Most common adverse reactions (≥20%), including laboratory abnormalities, with JEMPERLI in combination with carboplatin and paclitaxel in patients with EC are decreased hemoglobin, increased creatinine, peripheral neuropathy, decreased white blood cell count, fatigue, nausea, alopecia, decreased platelets, increased glucose, decreased lymphocytes, decreased magnesium, decreased neutrophils, increased aspartate aminotransferase (AST), arthralgia, rash, constipation, diarrhea, increased alanine aminotransferase (ALT), decreased potassium, decreased albumin, decreased sodium, increased alkaline phosphatase, abdominal pain, dyspnea, decreased appetite, increased amylase, decreased phosphate, urinary tract infection, and vomiting. ( 6.1 ) • Most common adverse reactions (≥20%) with JEMPERLI as a single agent in patients with dMMR solid tumors are fatigue/asthenia, anemia, diarrhea, and nausea. Most common Grade 3 or 4 laboratory abnormalities (≥2%) are decreased lymphocytes, decreased sodium, increased alkaline phosphatase, and decreased albumin.
Source: FDA drug label, GlaxoSmithKline LLC, effective September 2, 2025 (SPL set 095eab9f-545a-4f12-bfb7-19477fb901a5), via openFDA; the full label on DailyMed
What do FAERS reports show?
2,264 reports list dostarlimab among the medicines taken, each a report of something that happened, not proof the medicine caused it; 274 are coded as a death and 878 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 21 reactions below, 17 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?
- Dostarlimab: 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