Objective: Although topical decongestants and anesthetics are widely used in preparation for nasal endoscopy, no controlled trials have evaluated the effects of these agents on olfaction.
Study design: Randomized double-blinded controlled trial.
Setting: Tertiary referral hospital.
Materials and methods: The authors recruited 72 healthy subjects and randomly assigned them to 1 of 4 groups (control, phenylephrine group, lidocaine group, and both agents). After baseline tests with the Korean version of Sniffin' Stick Test II (KVSS II), topical agents were applied to each nostril. Fifteen minutes later, repeat tests were carried out. Pre- and postspray results of the olfactory tests were compared, and the differences among groups were analyzed.
Results: The mean ± SD prespray KVSS II score of the study group was 30.2 ± 3.8, and there were no statistically significant differences among the study groups (P = .353). Mean ± SD pre- and postspray KVSS II scores were 29.0 ± 3.5 and 30.7 ± 3.7 (P = .128) in the control group, 30.6 ± 3.6 and 31.7 ± 3.3 (P = .262) in the phenylephrine group, and 31.4 ± 3.6 and 32.1 ± 3.1 (P = .557) in the lidocaine group, respectively. In the phenylephrine and epinephrine spray group, the mean ± SD pre- and postspray scores were 29.9 ± 4.4 and 31.3 ± 3.7 (P = .071), respectively.
Conclusions: Neither topical intranasal phenylephrine nor lidocaine use affected the results of the olfactory test, even when the agents were used in combination.