Table 2. Among patients who received an antibiotic, first antibiotic prescribed after antibiotic allergy documentation^1,2.

Documentation (N)	Penicillins (%)	Cephalosporins (%)	Fluoroquinolones (%)	Clindamycin (%)	Vancomycin (%)	Macrolides (%)
ALL PATIENTS (161,658)
Beta-lactam allergy (21,196)	3.5*	4.7*	24.7*	11.0*	1.5*	43.5*
No beta-lactam allergy (140,462)	21.9*	16.6*	16.4*	2.9*	0.3*	33.1*
WAS A SPECIFIC BETA- LACTAM ALLERGEN IDENTIFIED? (21,196)
Specific beta-lactam (8,811)	5.3*	5.3*	23.5*	10.3ǂ	1.5	43.0
No specific beta-lactam (12,302)	2.2*	4.3*	25.8*	11.5ǂ	1.4	43.5
WERE CHARACTERISTICS OF BETA-LACTAM REACTION DOCUMENTED? (21,196)
Documented (4,403)	6.1*	7.3*	24.2	10.4	1.2	40.3*
Not documented (16,793)	2.8*	4.0*	24.8	11.1	1.5	44.4*
WAS BETA-LACTAM REACTION HIGH RISK? (4,403)
High risk reaction (646)	3.6ǂ	4.2ǂ	28.0Ϯ	12.0	1.1	41.8
Not a high risk reaction (3,660)	6.6ǂ	7.8ǂ	23.7Ϯ	10.2	1.2	39.9

*p < 0.001;

^ǂ p < 0.01;

^Ϯ p < 0.05

¹ Rows do not add up to 100 because other antibiotic classes not displayed

² Only patients who received an antibiotic after allergy documentation were included. For patients who did not have a beta-lactam allergy documented, the first antibiotic prescribed is the first antibiotic received during the study period