Patients with incomplete facial paralysis may recover or heal within one to two months, while those with complete facial paralysis generally need two to eight months, or even a year to recover, often leaving sequelae. Recovery of taste within a week indicates a good prognosis. Young patients have a better prognosis, while elderly patients with mastoid pain, diabetes, hypertension, cerebral arteriosclerosis, myocardial infarction, and other conditions have a poorer prognosis. We generally use electromyography (EMG) to examine and predict outcomes. If a patient with complete facial paralysis shows an M-wave amplitude in the affected area's EMG action potentials that is 30% or more of the normal value within seven days of the illness, they may fully recover within two months. If optic nerve potentials appear within ten days after the onset of the illness, the recovery tends to be slow.