The American Veterinary Medical Association issued new clinical guidance for veterinarians on diagnosing and managing mold-related illness in dogs in February 2026, citing a 40 percent increase in reported cases over the prior two years that correlates with rising water damage incidents nationwide.
The guidance identifies the most common presenting symptoms of mold illness in dogs: persistent coughing and wheezing, lethargy and exercise intolerance, loss of appetite, nasal discharge, skin irritation and excessive scratching, and in severe cases, neurological signs including tremors and loss of coordination.
Dogs are particularly vulnerable to mold exposure because they spend more time at floor level, where mold spore concentrations are highest, and because their grooming behavior leads to direct ingestion of spores and mycotoxins. Small-breed dogs and brachycephalic breeds face elevated respiratory risk.
The AVMA guidance recommends that veterinarians ask about recent water damage or musty odors in the home when evaluating dogs with unexplained respiratory or neurological symptoms. It also recommends that veterinarians advise clients to have their homes tested for mold when a pattern of unexplained illness is identified.
Critically, the guidance notes that dogs often show symptoms before human family members, making them effective early warning indicators of mold contamination. Veterinarians are encouraged to communicate this to clients and to recommend environmental assessment when mold illness is suspected.
