Print OverviewDysarthria occurs when the muscles you use for speech are weak or you have difficulty controlling them. Dysarthria often causes slurred or slow speech that can be difficult to understand. Common causes of dysarthria include nervous system disorders and conditions that cause facial paralysis or tongue or throat muscle weakness. Certain medications also can cause dysarthria. Treating the underlying cause of your dysarthria may improve your speech. You may also need speech therapy. For dysarthria caused by prescription medications, changing or discontinuing the medications may help.Products & ServicesBook: Mayo Clinic Family Health Book, 5th EditionNewsletter: Mayo Clinic Health Letter — Digital EditionShow more products from Mayo Clinic SymptomsSigns and symptoms of dysarthria vary, depending on the underlying cause and the type of dysarthria. They may include: Slurred speech Slow speech Inability to speak louder than a whisper or speaking too loudly Rapid speech that is difficult to understand Nasal, raspy or strained voice Uneven or abnormal speech rhythm Uneven speech volume Monotone speech Difficulty moving your tongue or facial muscles When to see a doctorDysarthria can be a sign of a serious condition. See your doctor if you have sudden or unexplained changes in your ability to speak. Request an appointment CausesIn dysarthria, you may have difficulty moving the muscles in your mouth, face or upper respiratory system that control speech. Conditions that may lead to dysarthria include: Amyotrophic lateral sclerosis (ALS, or Lou Gehrig's disease) Brain injury Brain tumor Cerebral palsy Guillain-Barre syndrome Head injury Huntington's disease Lyme disease Multiple sclerosis Muscular dystrophy Myasthenia gravis Parkinson's disease Stroke Wilson's disease Some medications, such as certain sedatives and seizure drugs, also can cause dysarthria. ComplicationsBecause of the communication problems dysarthria causes, complications can include: Social difficulty. Communication problems may affect your relationships with family and friends and make social situations challenging. Depression. In some people, dysarthria may lead to social isolation and depression. By Mayo Clinic Staff Request an appointment Diagnosis & treatment May 17, 2022 Print Share on: FacebookTwitter Show references Daroff RB, et al., eds. Bradley's Neurology in Clinical Practice. 7th ed. Elsevier; 2016. https://www.clinicalkey.com. Accessed April 10, 2020. Dysarthria. American Speech-Language-Hearing Association. https://www.asha.org/public/speech/disorders/dysarthria/. Accessed April 6, 2020. Maitin IB, et al., eds. Current Diagnosis & Treatment: Physical Medicine & Rehabilitation. McGraw-Hill Education; 2020. https://accessmedicine.mhmedical.com. Accessed April 10, 2020. Dysarthria in adults. American Speech-Language-Hearing Association. https://www.asha.org/PRPPrintTemplate.aspx?folderid=8589943481. Accessed April 6, 2020. Drugs that cause dysarthria. IBM Micromedex. https://www.micromedexsolutions.com. Accessed April 10, 2020. Lirani-Silva C, et al. Dysarthria and quality of life in neurologically healthy elderly and patients with Parkinson's disease. CoDAS. 2015; doi:10.1590/2317-1782/20152014083. Signs and symptoms of untreated Lyme disease. Centers for Disease Control and Prevention. https://www.cdc.gov/lyme/signs_symptoms/index.html. Accessed April 6, 2020. Neurological diagnostic tests and procedures fact sheet. National Institute of Neurological Disorders and Stroke. https://www.ninds.nih.gov/Disorders/Patient-Caregiver-Education/Fact-Sheets/Neurological-Diagnostic-Tests-and-Procedures-Fact. Accessed April 6, 2020. Related Associated Procedures CT scan EEG (electroencephalogram) Electromyography (EMG) Lumbar puncture (spinal tap) MRI Urinalysis Show more associated procedures Products & Services Book: Mayo Clinic Family Health Book, 5th Edition Newsletter: Mayo Clinic Health Letter — Digital Edition Show more products and services from Mayo Clinic DysarthriaSymptoms & causesDiagnosis & treatmentDoctors & departments Advertisement Mayo Clinic does not endorse companies or products. Advertising revenue supports our not-for-profit mission. Advertising & Sponsorship Policy Opportunities Ad Choices Mayo Clinic Press Check out these best-sellers and special offers on books and newsletters from Mayo Clinic Press. Mayo Clinic on Incontinence - Mayo Clinic PressMayo Clinic on IncontinenceNEW – Future Care - Mayo Clinic PressNEW – Future CareMayo Clinic on Hearing and Balance - Mayo Clinic PressMayo Clinic on Hearing and BalanceFREE Mayo Clinic Diet Assessment - Mayo Clinic PressFREE Mayo Clinic Diet AssessmentMayo Clinic Health Letter - FREE book - Mayo Clinic PressMayo Clinic Health Letter - FREE book CON-20371980 Patient Care & Health Information Diseases & Conditions Dysarthria