The mild, warm wet weather this month lead to lots of enquiries about dogs eating mushrooms and we have had several fatal cases.

Many mushrooms just cause gastrointestinal signs but some that are less common, cause delayed (> 6 hours) gastrointestinal signs (which are usually severe), renal and/or liver failure. There are also mushrooms that contain psilocybin (e.g. magic mushrooms) or ibotenic acid (which causes gastrointestinal and CNS signs). Also, the spores of puffballs can cause respiratory signs.

The main mushroom toxin causing problems in dogs currently is muscarine (which is found in Clitocybe species and Inocybe species, for example). These mushrooms cause rapid and dramatic signs with thick, ropey hypersalivation, vomiting, diarrhoea, bradycardia and collapse. The fatal cases we have seen in the past few weeks have involved muscarine-containing mushrooms. Atropine is recommended for muscarine poisoning but contraindicated in ibotenic acid poisoning.

There are thousands of different species of mushrooms and their appearance can vary depending on the stage of growth and decay, so it requires specialist advice to reliably identify mushrooms. We work with the Fungus Conservation Trust and can arrange to have mushrooms identified and provide appropriate and specific treatment advice. If you have a case involving ingestion of a mushroom, please contact us for details. We will send you guidelines on taking images and a questionnaire to provide additional information that can aid identification. Even without images or samples we may be able to narrow down the type of toxin involved by clinical signs. Please helps us collect data on clinical signs and outcome in animals with identified mushroom ingestion and let us know the outcome of these cases.