Risks of minoxidil toxicity for household pets

Background Topical minoxidil is a popular over-the-counter treatment for hair loss, but it is highly toxic to pets, particularly cats. Severe and sometimes fatal outcomes have occurred, yet public awareness remains limited. We assessed trends in pet exposures to topical minoxidil and their outcomes alongside public interest.Methods We reviewed reports of exposure to topical minoxidil in pets submitted to the ASPCA Poison Control (APC) 2013–2024, excluding oral formulations or co-exposures. Google Trends data for “topical minoxidil” were used to assess normalized public interest (0–100 scale). The annual proportion of APC reports involving topical minoxidil was similarly normalized and compared to Google Trends using Pearson correlation.Results The APC received a total of 701 calls concerning minoxidil (62% cats). Toxicity developed in 46%. Among 28 cases followed to known outcome, five fatalities occurred —all in cats. Most exposures involved oral ingestion through exploratory behavior. Minoxidil-related cases increased by nearly ten-fold over the study period and increased in proportion to total APC cases. Google Trends showed a parallel increase, strongly correlating with APC reports (r2 = 0.79).Conclusion Topical minoxidil poses a growing, potentially fatal risk to pets. Increased public education and clearer product labeling are urgently needed.