Background and Importance Infliximab can cause infusion-related reactions like delayed hypersensitivity or anaphylactic shock. Using corticosteroids or antihistamines as premedication can reduce adverse drug reactions (ADRs) frequency.

Aim and Objectives To evaluate premedication impact on ADRs occurrence in patients with inflammatory bowel disease (IBD) who received infliximab.

Material and Methods Retrospective observational study in patients with IBD who received intravenous infliximab from January 2016 to December 2020. The variables collected were: demographic (age, sex), clinical (type of inflammatory bowel disease, Harvey index Bradshaw in Crohn's disease, Mayo index in ulcerative colitis), premedication used (type of drug and number of administrations), number of infliximab administrations and the ADRs characteristics. For the statistical analysis, mean, standard deviation and absolute risk were used.

Results 119 patients were included with an average age of 46 ± 17 years and 42% women. 42 patients had ulcerative colitis, 74 patients had Crohn's disease, and 3 patients had indeterminate colitis. In the base line study, patients with Crohn's disease had Harvey score mean of 7.1 ± 3.7 and patients with ulcerative colitis had partial Mayo score mean of 3.7 ± 2.3. A total of 1909 infliximab infusions were administrated and premedication was used in 1185 administration in 80 patients. Premedication was administrated in 21.2% (n=17) during induction phase, in 32.5% (n=26) during maintenance phase, and in 46.3% (n=37) during both phases. Glucocorticoids were used as a premedication in 97.5% of cases.

25 ADRs were recorded in 21 patients. The patients (n=17) who received premedication had 21 ADRs and an absolute risk of 10.3% (CI95, 0.7%-19.8%). In the other group, the patients who did not receive premedication had 4 ADRs (n=4) and an absolute risk of 21.3% (CI95, 12.3%- 30.2%). 44% of ADRs occurred in induction phase and 56% in maintenance phase. The main symptoms of ADRS registered were skin manifestations (n=16), cardiovascular (n=6) and respiratory symptoms (n=3).

Conclusion and Relevance No lower absolute ADR risk were observed in patients who received premedication compared to patients who did not receive premedication. More studies are needed in order to evaluate the impact of premedication on ADRs occurrence.

Conflict of Interest No conflict of interest