Allergic inhalant dermatitis attributable to marijuana exposure in a dog

Exposure to marijuana was believed to be responsible for clinical signs consistent with allergic inhalant dermatitis in a dog. The dog had facial and pedal pruritus associated with bilateral ocular discharge. Clinical signs resolved when the dog was kenneled, but returned when the dog was returned to its home. The results of intradermal skin testing, using a standard tray of 51 inhalant extracts, did not adequately account for the dog's clinical signs. Later, the owners indicated that previous residents of the owners' home had cultivated marijuana intensively inside and outside of the home. Intradermal skin testing with a source of marijuana pollen extract was performed, yielding a positive reaction in the dog and a negative reaction in another dog without clinical or historical evidence of allergic inhalant dermatitis. The affected dog was treated successfully and exclusively by hyposensitization with marijuana pollen extract.