A retrospective evaluation of mushroom ingestions in 421 dogs in Norway (2011-2022).

Background: Mushroom poisoning may result in a variety of signs ranging from mild, mostly gastroenteritis, to organ failure and death. To increase the knowledge of prevalence, treatment and outcome in dogs, information regarding mushroom ingestion was collected.

Materials and methods: This retrospective study analysed all inquiries of mushroom ingestion in dogs to the Norwegian Poison Information Center from 2011 to 2022. Mushrooms were identified by a mycologist or Norwegian-certified mushroom expert. Differences in mushroom species, clinical findings, treatments and outcome were evaluated.

Results: A total of 421 mushroom ingestions in dogs were included. The mushrooms were identified as non-poisonous in 45% of cases. The most frequently involved toxin group was gastrointestinal mushrooms, followed by muscarinic mushrooms and mushrooms containing isoxazoles. About 64% of cases were managed at home, 33% were hospitalised and received treatment, and 3% were observed by a veterinarian without treatment. The survival rate was 98.6%, with death occurring after ingestion of Amanita muscaria, Cortinarius rubellus, Amanita virosa, Clitocybe rivulosa and Inocybe sp.

Conclusions: This study demonstrated the importance of rapid and accurate identification of the mushroom. This could prevent delays in therapeutic intervention and avoid unnecessary treatment of these dogs. With early, correct identification of mushrooms, our results demonstrated a good prognosis for dogs after ingestion.