RT Journal Article SR Electronic T1 Penicillin allergy JF Canadian Medical Association Journal JO CMAJ FD Canadian Medical Association SP E231 OP E231 DO 10.1503/cmaj.181117 VO 191 IS 8 A1 McCullagh, David J. A1 Chu, Derek K. YR 2019 UL http://www.cmaj.ca/content/191/8/E231.abstract