Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2021 May;35(3):1604-1611.
doi: 10.1111/jvim.16113. Epub 2021 Apr 4.

Nebulized dexamethasone sodium phosphate in the treatment of horses with severe asthma

Selena de Wasseige  1 , Khristine Picotte  1 , Jean-Pierre Lavoie  1
Affiliations

Nebulized dexamethasone sodium phosphate in the treatment of horses with severe asthma

Selena de Wasseige et al. J Vet Intern Med. 2021 May.

Abstract

Background: A study reported low systemic availability of injectable dexamethasone nebulized to healthy horses using the Flexineb mask. When used in horses with severe asthma and a different nebulizer, lack of efficacy and cortisol suppression were observed.

Hypothesis: Nebulized dexamethasone is as effective as PO administration for the treatment of severe asthma in horses.

Animals: Twelve horses with severe asthma from a research herd.

Methods: Randomized clinical trial. Horses were divided into 2 groups and received 5 mg of dexamethasone sodium phosphate by nebulization using a Flexineb mask (NE, n = 6) or PO (OR, n = 6) q24h for 7 days. Lung function and serum cortisol concentrations were evaluated at baseline, after 4 days of treatment (D4) and 1 day after the last treatment (D8). Data were analyzed using linear mixed models with Benjamini-Hochberg adjustments.

Results: Lung resistance significantly improved at D4 (mean decrease ± SD, -1.5 ± 0.45 cm H₂O/L/s; 95% confidence interval [CI], -2; -0.6) and D8 (-1.4 ± 0.45 cm H₂O/L/s; 95% CI, -2.4; -0.5) compared to baseline in the OR group only (P = .004 and .01, respectively). Serum cortisol concentration was significantly decreased at D4 and D8 for both groups (maximum decrease, -1.2 ± 0.3 μg/dL; 95% CI, -1.9; -0.6 at D4 for NE group and -2.2 ± 0.3 μg/dL; 95% CI, -2.8; -1.6 at D8 for OR group; P < .001).

Conclusions and clinical importance: Oral, but not nebulized dexamethasone is an effective therapy for horses with severe asthma and both treatment modalities inhibit the hypothalamic-pituitary-adrenal axis.

Keywords: corticosteroids; cortisol; heaves; hypothalamic-pituitary-adrenal axis suppression; inhalation; lung; recurrent airway obstruction.

PubMed Disclaimer

Conflict of interest statement

Nortev provided funding and equipment for this experiment.

Figures

FIGURE 1
FIGURE 1
Transpulmonary pressure (P L; A), lung resistance (R L; B) and lung elastance (E L; C) (the horizontal lines represent the mean ± SD) at baseline, on treatment day 4, and 1 day after the last treatment (day 8) in horses with severe asthma treated with nebulized (black circles; n = 6) or PO (white circles; n = 6) dexamethasone (5 mg q24h). The dotted line represents values expected from healthy horses. * represents significant difference from baseline
FIGURE 2
FIGURE 2
Transpulmonary pressure (P L; A), lung resistance (R L; B) and lung elastance (E L; C) (the horizontal lines represent the mean ± SD) before and 10 minutes after administration of N‐butylscopolammonium IV (0.03 mg/kg) on day 8 to horses with severe asthma treated with nebulized (black circles; n = 6) or PO (white circles; n = 6) dexamethasone (5 mg q24h). The dotted line represents values expected from healthy horses. * represents significant difference from baseline
FIGURE 3
FIGURE 3
Concentration of serum cortisol at baseline, on day 4 and day 8 (the horizontal lines represent the mean ± SD) in horses with severe asthma treated with nebulized (black circles; n = 6) or PO (white circles; n = 6) dexamethasone (5 mg q24h). * represents significant difference from baseline
See this image and copyright information in PMC

References

    1. Hotchkiss JW, Reid SW, Christley RM. A survey of horse owners in Great Britain regarding horses in their care. Part 2: risk factors for recurrent airway obstruction. Equine Vet J. 2007;39:301‐308. - PubMed
    1. Vandenput S, Istasse L, Nicks B, Lekeux P. Airborne dust and aeroallergen concentrations in different sources of feed and bedding for horses. Vet Q. 1997;19:154‐158. - PubMed
    1. Couetil LL, Cardwell JM, Gerber V, et al. Inflammatory airway disease of horses—revised consensus statement. J Vet Intern Med. 2016;30:503‐515. - PMC - PubMed
    1. Pirie RS. Recurrent airway obstruction: a review. Equine Vet J. 2014;46:276‐288. - PubMed
    1. Leclere M, Lavoie‐Lamoureux A, Lavoie JP. Heaves, an asthma‐like disease of horses. Respirology. 2011;16:1027‐1046. - PubMed

Publication types