A bulge on the French Bulldog's neck may be caused by hernia, skin disease, etc. It is best to take your dog to a pet hospital for examination and treatment to avoid worsening of the condition. Generally, hernias or tumors require surgical treatment, otherwise the bulge will get bigger and bigger, which will affect the dog's health. If it is a skin disease, just bathe the dog and deworm it on time, and then apply medicine to treat the skin disease.