Infusion-related reactions to infliximab in patients with rheumatoid arthritis in a clinical practice setting: relationship to dose, antihistamine pretreatment, and infusion number.
OBJECTIVE
We describe infusion-related reactions to infliximab (during infusion or within 1 hour postinfusion) in patients with active rheumatoid arthritis (RA) treated in a quaternary care center.


METHODS
We followed 113 patients for a mean of 60.6 +/- 28.9 weeks, obtaining 10.5 +/- 4.9 infusions per patient.


RESULTS
We observed 1183 infusions resulting in 104 infusion reactions (8.8%). All reactions resolved within several hours following cessation of the infusion and none was serious enough to warrant hospitalization. Reactions included allergic reactions (pruritus, urticaria) in 4.2% of infusions, cardiopulmonary (hypotension, hypertension, tachycardia) in 3.0%, and miscellaneous reactions (headache, nausea, vomiting) in 2.0%. Reactions occurred in 8.0% of 3 mg/kg infusions and in 10.3% of 5 mg/kg infusions. Reactions occurred in 13.2% of infusions that involved antihistamine pretreatment compared to only 7.5% of infusions that involved no pretreatment. At both infliximab doses, there was a similar frequency of infusion reactions in patients pretreated due to a previous infusion (12.6%) compared to those pretreated strictly based on infusion number (14.7%). A number of the reactions involving antihistamine pretreatment may be explained by known side effects of diphenhydramine, including headache, dizziness, nausea, and palpitations.


CONCLUSIONS
Infusion-related reactions to infliximab were infrequent, rarely severe, and easily manageable. The frequency of reactions was equivalent in patients treated with 3 mg/kg compared to 5 mg/kg. Reactions were significantly more frequent in infusions where patients were pretreated with the antihistamine diphenhydramine, compared to those not involving pretreatment.
Rebecca MacDonald Centre for Arthritis and Autoimmune Disease, Division of Advanced Therapeutics, Mount Sinai Hospital, University of Toronto, Toronto, Ontario, Canada.
Michael J
MJ
Wasserman
Deborah A
DA
Weber
Judith A
JA
Guthrie
Vivian P
VP
Bykerk
Peter
P
Lee
Edward C
EC
Keystone
D000293:Adolescent; D000328:Adult; D000368:Aged; D000911:Antibodies, Monoclonal / Q000009:adverse effects / Q000627:therapeutic use; D018501:Antirheumatic Agents / Q000009:adverse effects / Q000627:therapeutic use; D001172:Arthritis, Rheumatoid / Q000188:drug therapy*; D004155:Diphenhydramine / Q000627:therapeutic use*; D004305:Dose-Response Relationship, Drug; D006634:Histamine H1 Antagonists / Q000627:therapeutic use*; D006801:Humans; D006967:Hypersensitivity / Q000276:immunology; D000069285:Infliximab; D007262:Infusions, Intravenous / Q000009:adverse effects; D008875:Middle Aged; D010044:Outpatient Clinics, Hospital
D000911:Antibodies, Monoclonal; D018501:Antirheumatic Agents; D006634:Histamine H1 Antagonists; D004155:Diphenhydramine; D000069285:Infliximab