Are dogs allergic to plant fungul spores?

by Moya Joubert
(Tacoma, WA)

I have been working with my vet for about 2 years to try to resolve the itching problem for 2 of my dogs. We have done the food allergy routine but they got no relief. Then I did a dust mite treatment and still no relief.

They itch year round (they are on Frontline year round too) and they have a dog door so they freely go in and out of the house. I have stopped using anything but natural cleaning chemicals. I have even removed outdoor furniture that I thought might have fireproofing chemicals on it.

About 2 years ago I noticed my red tip photinia, roses, pears, and hawthorn all are dropping leaves and have spots on leaves that I am pretty sure is caused by the fungus Entomosporium (I brought into my lab to take a peak under the microscope). My retriever used to drag her body along the photnia hedge (and her greatest symptoms appeared on her belly) and my mix breed used to just stand under the hedge to talk with neighbor dogs (and she constantly licks her feet as her symptom). I have fenced off the hedge from the yard now and am slowly removing it (70 feet long and 10 ft high) so the dogs no longer have direct contact with the leaves (I put the fence up about 5 days ago).

Have you heard of dogs being allergic to plant fungi? If I have removed the source how long before I would see improvement in the dogs?

My vet says that allergy testing is very expensive and I have very limited funds but I'm at wits end and I don't want my dogs on prednisone the rest of their lives - do you think I need to resort to allergy testing at this point.

I have another dog who stays in the house most of the time and never lays on the carpet; always on furniture or me. Thank you for any help that you can give me.

Vet Suggestion Dog Allergy Fungal Spores

Hi Moya,

I can’t say I’ve head of dogs being allergic to plant fungi in particular, but I wouldn’t be surprised at all if it was a possibility. Keep in mind that I’m not a veterinary dermatologist, but I’ve always told my clients that dogs can essentially be allergic to anything, which is why it can be so difficult to definitively diagnose allergies.

If your dogs are reacting to the fungal spores, I wouldn’t expect their condition to improve until all the affected plants are removed from the environment. The fence alone will probably not be sufficient since the spores would surely spread into the rest of the yard with the wind, etc. The spores that are in your yard would also need to break down or disappear before your dogs would stop reacting. How long would this take? Your guess is as good as mine.

Are your dogs’ problems seasonal? If the plant fungi are to blame I would expect the allergies to be at their worst when the plants are most affected (e.g., in the summer).

Allergy testing can be expensive and is not fool proof. For example, the panel may not include the allergen(s) to which your dogs are reacting. However, it is the best method we have available to determine what a pet is allergic to and for developing an appropriate treatment plan.

If allergy testing is not in the cards and your dogs need year-round treatment with prednisone to keep them comfortable, talk to your veterinarian. There are other drugs (e.g., cyclosporine) that can be more effective and safer for long term use.

Good luck,


Jennifer Coates, DVM