A Randomized Controlled Trial to Assess the Effect of Lidocaine Administered via Throat Spray and Nebulization in Patients with Refractory Chronic Cough.

Abstract

BACKGROUND:

Refractory chronic cough (RCC) is a debilitating condition for which there are no licensed treatments. Lidocaine is a nonselective inhibitor of voltage-gated sodium channels with potential antitussive effects, but randomized placebo-controlled studies evaluating its efficacy in RCC are lacking.

OBJECTIVE:

To investigate the efficacy of nebulized lidocaine and lidocaine throat spray versus matched placebos in RCC.

METHODS:

This was a randomized, double-blind, double-dummy, placebo-controlled, 3-way crossover study, comparing the effect of single doses of nebulized lidocaine with lidocaine delivered by a throat spray and matched placebo. The primary end point was cough frequency over the 10 hours following treatment. Secondary end points were visual analog scale scores for urge-to-cough and cough severity; an exploratory analysis evaluated hourly cough rates up to 5 hours after treatment.

RESULTS:

Twenty-six subjects with RCC were recruited (22 females; mean age, 53.5 ± 12.1 years; FEV1 %predicted, 105.2 ± 16.8 L; forced vital capacity %predicted, 112.4 ± 18 L). Lidocaine throat spray, but not nebulized lidocaine, significantly reduced 10-hour cough frequency as compared with placebo (throat spray, 22.6 coughs/h; nebulization, 26.9 coughs/h; and placebos, 27.6 coughs/h; P = .04,). Lidocaine throat spray showed the greatest effect on cough compared with placebo in the first hour after administration (31.7 coughs/h vs 74.2 coughs/h; P = .004). Both nebulizer and spray treatments significantly alleviated urge-to-cough and cough severity visual analog scale scores compared with placebo (P < .05). There were no serious adverse events associated with lidocaine therapy.

CONCLUSIONS:

Lidocaine throat spray was effective in reducing cough frequency in patients with RCC. Voltage-gated sodium channel inhibitors applied to pharynx have potential as therapies for RCC.

• Authors: Rayid Abdulqawi, Imran Satia, Yoshihiro Kanemitsu, Saifudin Khalid, Kimberley Holt, Rachel Dockry, Ashley A Woodcock, Jaclyn A Smith
• Journal: The journal of allergy and clinical immunology. In practice (J Allergy Clin Immunol Pract) Vol. 9 Issue 4 Pg. 1640-1647 (04 2021) ISSN: 2213-2201 [Electronic] United States
• PMID: 33259976 (Publication Type: Journal Article, Randomized Controlled Trial, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2020 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

Chemical References

• Anesthetics, Local
• Lidocaine

Topics

• Adult
• Aged
• Anesthetics, Local
• Cough (drug therapy)
• Cross-Over Studies
• Double-Blind Method
• Female
• Humans
• Lidocaine
• Middle Aged
• Nebulizers and Vaporizers
• Pharynx