Effect of topical diphenhydramine on the laryngeal chemoreflex.
OBJECTIVE
To study diphenhydramine nebulization as a clinically applicable method for blunting laryngeal chemoreflex (LCR)-associated apnea.


METHODS
Fourteen piglets aged 15 to 18 days were studied. In 7 piglets, diphenhydramine hydrochloride (5.0 mg/kg) was nebulized onto the laryngeal mucosa after a baseline response was obtained.


RESULTS
After a 10-minute waiting period, the mean +/- SD LCR-induced apnea duration decreased from 29 +/- 13 seconds in the control animals to 15 +/- 5 seconds in the treated group (P = .02, 1-factor analysis of variance). After 1 hour, no treatment effect was seen.


CONCLUSIONS
Nebulization of diphenhydramine can effectively reduce LCR-induced apnea for a short time. Nebulization of longer-acting agents may provide an effective prophylaxis of LCR-induced apnea.
Boyer
H C
HC
University of Minnesota, Minneapolis, USA.
Downs
D H
DH
Goding
G S
GS
Pernell
K J
KJ
D000287:Administration, Topical; D000336:Aerosols; D000818:Animals; D001049:Apnea / Q000503:physiopathology; D001794:Blood Pressure; D004155:Diphenhydramine / Q000008:administration & dosage* / Q000494:pharmacology; D004576:Electromyography; D006634:Histamine H1 Antagonists / Q000008:administration & dosage* / Q000494:pharmacology; D007821:Laryngeal Muscles / Q000502:physiology; D007830:Larynx / Q000187:drug effects / Q000502:physiology* / Q000503:physiopathology; D012018:Reflex / Q000187:drug effects*; D012119:Respiration; D012965:Sodium Chloride / Q000008:administration & dosage; D013552:Swine
D000336:Aerosols; D006634:Histamine H1 Antagonists; D012965:Sodium Chloride; D004155:Diphenhydramine