Signs / Lack of efficacy (flea)
Lack of efficacy (flea): medicines most often named in FDA reports
Reports received through June 26, 2026. Data and limitations.
8,324Total reports
7,220Dog reports
1,096Cat reports
Species named in reports
These are the ingredients most often named in the supplied reports, displayed alphabetically. One report may name multiple ingredients; counts must not be used to compare products.