Side effects of medications that act on the central nervous system, such as narcotics, phenytoin, or carbamazepine
Depending on its cause, dysarthria may develop slowly or occur suddenly.
People with dysarthria have trouble making certain sounds or words.
Their speech is poorly pronounced (such as slurring), and the rhythm or speed of their speech changes. Other symptoms include:
Sounding as though they are mumbling
Speaking softly or in a whisper
Speaking in a nasal or stuffy, hoarse, strained, or breathy voice
A person with dysarthria may also drool and have problems chewing or swallowing. It may be difficult to move the lips, tongue, or jaw.
Exams and Tests
The health care provider will take a medical history and perform a physical examination. Family and friends may need to help with the medical history.
A procedure called laryngoscopy may be done. During this procedure, a flexible viewing tube called a laryngoscope is placed in the mouth and throat to view the voice box.
Tests that may be done if the cause of the dysarthria is unknown include:
Blood tests for toxins or vitamin levels
Imaging tests, such as an MRI or CT scan of the brain or neck
Nerve conduction studies and electromyogram to check the electrical function of the nerves or muscles
Swallowing study, which may include x-rays and drinking a special liquid
You may need to be referred to a speech and language therapist for testing and treatment. Special skills you may learn include:
Safe chewing or swallowing techniques, if needed
To avoid conversations when you are tired
To repeat sounds over and over again so you can learn mouth movements
To speak slowly, use a louder voice, and pause to make sure other people understand
What to do when you feel frustrated while speaking
You can use many different devices or techniques to help with speech, such as:
Computers to type out words
Flip cards with words or symbols
Special computer programs that allow you to create spoken words by typing words or clicking on symbols
Surgery may help people with dysarthria.
Depending on the cause of dysarthria, symptoms may improve, stay the same, or get worse slowly or quickly.
Patients with amyotrophic lateral sclerosis (ALS or Lou Gehrig disease) eventually lose the ability to speak.
Few people with Parkinson disease or multiple sclerosis lose the ability to speak.
Dysarthria caused by medication or poorly fitting dentures can be reversed.
Dysarthria caused by a stroke or brain injury will not get worse, and may improve.
Dysarthria after surgery to the tongue or voice box should not get worse, and may improve with therapy.
When to Contact a Medical Professional
Call your health care provider if you have:
Chest pain, chills, fever, shortness of breath, or other symptoms of pneumonia
Coughing or choking
Difficulty speaking to or communicating with other people
Feelings of sadness or depression
Kirshner HS. Language and speech disorders: motor speech disorders: dysarthria and apraxia of speech. In: Daroff RB, Fenichel GM, Jankovic J. Mazziotta JC, eds. Bradley's Neurology in Clinical Practice. 6th ed. Philadelphia, PA: Saunders Elsevier; 2012:chap 12B.
Kortte JH, Palmer JB. Speech and language disorders. In: Frontera WR, Silver JK, Rizzo TD Jr., eds. Essentials of Physical Medicine and Rehabilitation. 3rd ed. Philadelphia, PA: Saunders Elsevier; 2014:chap 154.
Mahler LA, Ramig LO. Intensive treatment of dysarthria secondary to stroke. Clin Linguist Phon. 2012;26:681-694.
Joseph V. Campellone, MD, Department of Neurology, Cooper University Hospital, Camden, NJ. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.