Facial swelling in dogs can be caused by various factors such as allergies, abscesses, dental problems, and tumors. Allergies can result from chemicals, foods, plants, insect bites, or medications. Severe allergic reactions may cause throat swelling, making it hard for the dog to breathe. Treatment includes antihistamines, steroids, or in severe cases, epinephrine. Abscesses, often from bites or wounds, cause sudden swelling, fever, and pain. They require immediate treatment like surgical drainage and antibiotics. Dental issues like infected teeth can also lead to abscesses and swelling, treated by tooth removal and antibiotics. Tumors, whether cancerous or not, can cause facial swelling and need early treatment, possibly surgery or radiotherapy. Other causes include cellulitis from skin infections and craniomandibular osteopathy, a rare condition in some breeds. Preventive measures and early detection are crucial. Always consult a vet if your dog's face is swollen.