Sudden slurred speech may be caused by physiological factors, acute pharyngeal lesions, acute cerebrovascular lesions and other factors. 1. Physiological factors: encounter some important things, the heart excessive tension, will lead to sudden speech slurred, only occasionally, should adjust the mind, eliminate the nervousness of the psychological, maintain a stable state of mind, usually be able to improve on their own. 2. Acute pharyngeal lesions: such as acute pharyngitis, acute tonsillitis, etc., the onset of a more acute, more serious infection, may cause stimulation of the vocal cords, affecting the vocal cords, there will be a slurred speech phenomenon, which may be accompanied by swelling and pain in the throat, foreign body sensation and other symptoms. 3. Acute cerebrovascular lesions: for example, acute cerebral infarction or acute cerebral hemorrhage may affect the language and brain area during acute attack, which may lead to unclear speech or even inability to speak normally, accompanied by nausea and vomiting, hemiplegia and other abnormal manifestations. Sudden slurring of speech, accompanied by other abnormal manifestations, it is recommended to consult a doctor for timely examination and treatment to avoid delaying the condition.