Due to the concentration of most immune cells in a dog's gut, an imbalance in the gut microbiome can trigger allergic reactions in dogs. Excessive immune responses may occur due to pollen, dust, bacteria, or fungal infections, leading to discomfort such as sneezing, watery eyes, hair loss, skin issues, and itching in dogs. Severe scratching due to symptoms can lead to secondary infections and potentially chronic conditions, warranting caution.

Since allergic conditions vary in factors and symptoms for each dog, it's important to focus on consistently monitoring and avoiding allergen exposure by thoroughly understanding the gut environment through microbiome analysis, rather than relying solely on medication.