What the label lists and what reports show
Abatacept side effects
Abatacept's FDA label: “Most common adverse events (≥10%) in RA are headache, upper respiratory tract infection, nasopharyngitis, and nausea.” FAERS holds 137,678 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 pain (21,928 reports).
- No generic listed
Check it at the source: the abatacept FDA label on DailyMed (effective November 13, 2025, E.R. Squibb & Sons, L.L.C.); 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 ORENCIA?ORENCIA may cause serious side effects, including: • infections. ORENCIA can make you more likely to get infections or make the infection that you have get worse. Some people have died from these infections. Call your healthcare provider right away if you have any symptoms of an infection. Symptoms of an infection may include: o fever o feel very tired o have a cough o have flu-like symptoms o warm, red, or painful skin • allergic reactions. Allergic reactions can happen to people who are treated with ORENCIA. Call your healthcare provider or go to the emergency room right away if you have any symptoms of an allergic reaction. Symptoms of an allergic reaction may include: o hives o swollen face, eyelids, lips, or tongue o trouble breathing • hepatitis B infection in people who carry the virus in their blood. […]
Source: FDA drug label, E.R. Squibb & Sons, L.L.C., effective November 13, 2025 (SPL set 0836c6ac-ee37-5640-2fed-a3185a0b16eb), via openFDA; the full label on DailyMed
What does the label list?
From the label: adverse reactionsMost common adverse events (≥10%) in RA are headache, upper respiratory tract infection, nasopharyngitis, and nausea.
Table 4: Most Common Adverse Reactions* During Placebo-Controlled RA Studies of Intravenous ORENCIA
| Reaction | Intravenous ORENCIA (n=1955) a | Placebo (n=989) b |
|---|---|---|
| Headache | 18% | 13% |
| Nasopharyngitis | 12% | 9% |
| Dizziness | 9% | 7% |
| Cough | 8% | 7% |
| Back pain | 7% | 6% |
| Hypertension | 7% | 4% |
| Dyspepsia | 6% | 4% |
| Urinary tract infection | 6% | 5% |
| Rash | 4% | 3% |
| Pain in extremity | 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 clinically significant adverse reactions are described elsewhere in the labeling: • Increased Risk of Infection with Concomitant Use with TNF Antagonists, Other Biologic RA/PsA Therapy, or JAK Inhibitors [see Warnings and Precautions (5.1) ] • Hypersensitivity Reactions [see Warnings and Precautions (5.2) ] • Infections [see Warnings and Precautions (5.3) ] • Increased Risk of Adverse Reactions When Used in Patients with Chronic Obstructive Pulmonary Disease (COPD) [see Warnings and Precautions (5.5) ] • Immunosuppression [see Warnings and Precautions (5.6) ] • Cytomegalovirus (CMV) and Epstein-Barr Virus (EBV) Reactivation in aGVHD Prophylaxis after Hematopoietic Stem Cell Transplant (HSCT) [see Warnings and Precautions (5.7) ] • Most common adverse events (≥10%) in RA are headache, upper respiratory tract infection, nasopharyngitis, and nausea. (6.1) • Most common adverse reactions (≥10%) in prophylaxis of aGVHD are anemia, hypertension, CMV reactivation/CMV infection, pyrexia, pneumonia, epistaxis, CD4 lymphocytes decreased, hypermagnesemia, and acute kidney injury. (6.1) To report SUSPECTED ADVERSE REACTIONS, contact Bristol-Myers Squibb at 1-800-721-5072 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. …
Source: FDA drug label, E.R. Squibb & Sons, L.L.C., effective November 13, 2025 (SPL set 0836c6ac-ee37-5640-2fed-a3185a0b16eb), via openFDA; the full label on DailyMed
What do FAERS reports show?
137,678 reports list abatacept among the medicines taken, each a report of something that happened, not proof the medicine caused it; 9,239 are coded as a death and 25,417 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, 6 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?
- Abatacept: 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