DOI
https://doi.org/10.18849/ve.v11i3.747Abstract
Question
In cats with eosinophilic airway inflammation does cyproheptadine compared with no treatment result in a reduction in severity of clinical signs?
Clinical bottom line
The category of research question was:
Treatment.
The number and type of study designs that were critically appraised were:
Four studies were evaluated: the first was a randomised, blinded, placebo-controlled, crossover study, the second was a randomised crossover study, the third was a non-randomised, controlled study, and the fourth a non-randomised, controlled study.
Critical appraisal of the selected papers meeting the inclusion criteria collectively provide zero/weak/moderate/strong evidence in terms of their experimental design and implementation:
Moderate.
The outcomes reported are summarised as follows…
In two of the four studies it was found that cyproheptadine was not useful in resolving the symptoms of feline airway inflammation. The third study showed that the concentration of cyproheptadine that completely blocked contractile effects of serotonin did not successfully cause a significant effect on contraction caused by muscarinic stimulation. The fourth study provided evidence that cyproheptadine could reduce serotonin-induced bronchoconstriction.
In view of the strength of evidence and the outcomes from the studies the following conclusion is made…
There is no current evidence to support that cyproheptadine monotherapy has any immediate benefit over no treatment for feline eosinophilic airway inflammation, and its use is not supported for this indication.
References
Norris, C.R., Boothe, D.M., Esparza, T., Gray, C. & Ragsdale, M. (1998). Disposition of cyproheptadine in cats after intravenous or oral administration of a single dose. American Journal of Veterinary Research. 59(1), 79–81. DOI: https://doi.org/10.2460/ajvr.1998.59.01.79
Padrid, P.A., Mitchell, R.W., Ndukwu, I.M., Spaethe, S., Shiou, P., Cozzi, P. & Leff, A. (1995). Cyproheptadine-induced attenuation of type-I immediate-hypersensitivity reactions of airway smooth muscle from immune-sensitized cats. American Journal of Veterinary Research. 56(1), 109–115. DOI: https://doi.org/10.2460/ajvr.1995.56.01.109
Reiche, R. & Frey, H. (1983). Antagonism of the 5-HT-induced bronchoconstriction in the cat. Archives internationales de pharmacodynamie et de thérapie, 263(1), 139–145.
Reinero, C.R., Decile, K.C., Byerly, J.R., Berghaus, R.D., Walby, W.F., Berghaus, L.J., Hyde, D.M., Schelegle, E.S. & Gershwin, L.J. (2005). Effects of drug treatment on inflammation and hyperreactivity of airways and on immune variables in cats with experimentally induced asthma. American Journal of Veterinary Research. 66(7), 1121–1127. DOI: https://doi.org/10.2460/ajvr.2005.66.1121
Schooley, E.K., McGee Turner, J.B., JiJi, R.D., Spinka, C.M. & Reinero, C.R. (2007). Effects of cyproheptadine and cetirizine on eosinophilic airway inflammation in cats with experimentally induced asthma. American Journal of Veterinary Research. 68(11), 1265–1271. DOI: https://doi.org/10.2460/ajvr.68.11.1265
Trzil J. (2020). Feline Asthma: Diagnostic and Treatment Update. The Veterinary Clinics of North America: Small Animal Practice. 50(2), 375–391. DOI: https://doi.org/10.1016/j.cvsm.2019.10.002
License
Copyright (c) 2026 Jillian Seeman, Rachael Kreisler, Jeffrey Norris
This work is licensed under a Creative Commons Attribution 4.0 International License.
Veterinary Evidence uses the Creative Commons copyright Creative Commons Attribution 4.0 International License. That means users are free to copy and redistribute the material in any medium or format. Remix, transform, and build upon the material for any purpose, even commercially - with the appropriate citation.
