Idiopathic trigeminal neuritis is common in dogs and uncommon in cats. The primary symptom of trigeminal neuritis is an inability to open and close the mouth. Your dog’s lower jaw may begin to dangle limply. He/she may also lose the ability to blink his eyes. In most cases, dogs don’t experience total paralysis of the facial muscles, especially not in the initial stages of the disease. Affected dogs will also have difficulty eating and drinking. Horner syndrome, facial paresis, and decreased facial sensation are also possible. A brain MRI may be recommended to rule out other causes, especially if other neurologic symptoms exist. The cause is unknown. Histopathologically, there is bilateral nonsuppurative inflammation and demyelination in the motor branches of the trigeminal nerve. Feed your dog soft, easily-chewed food. Raise his food bowl up so he can reach it more easily. Offer your dog water from a water bottle, such as that used to feed large rodents, since he may have problems drinking. Affected animals usually recover spontaneously within 3–4 wk. Permanent trigeminal neuralgia symptoms in dogs are very rare, however; it’s very likely that your dog will recovery full use of his facial muscles within a very short period of time. Medications (i.e. steroids) do not increase the speed of recovery.