Common causes of dysarthria are:

  • Stroke
  • Brain tumor or traumatic brain injury
  • Infection
  • Health problems that paralyze the face or cause weakness, such as Bell palsy
  • Brain diseases such as:
    • Alzheimer disease
    • Huntington chorea
    • Parkinson disease
  • Neuromuscular diseases such as:
    • Amyotrophic lateral sclerosis (ALS)
    • Cerebral palsy
    • Multiple sclerosis
    • Muscular dystrophy
    • Myasthenia gravis
  • Alcohol or substance use disorder
  • Surgery or weakness on the tongue
  • Structural problems, such as not wearing dentures
  • Side effects of medicines that act on the central nervous system

Risk Factors

This problem is more common in older adults. It is also more common in people who have any of the health problems that cause dysarthria.



A person with dysarthria may have:

  • Speech that sounds:
    • Slurred
    • Hoarse and breathy
    • Slow or fast and mumbling
    • Soft like whispering
    • Strained
    • Nasal
    • Suddenly loud
  • Drooling
  • Trouble chewing and swallowing


The doctor will ask about symptoms and health history. A physical exam will be done. It will focus on the muscles needed for speech.

Images may be taken of the brain. This can be done with:

  • X-rays
  • MRI scan
  • CT scan
  • PET scan
  • Single-photon emission computed tomography (SPECT) scan

The electrical function of nerves and muscles may be tested. This can be done with:

  • A nerve conduction study
  • An electromyogram



The goal of treatment is to help a person speak. The cause of dysarthria will need to be treated. Speech therapy will also be needed.


There are no known guidelines to prevent dysarthria. Managing long term health problems may help.

This content is reviewed regularly and is updated when new and relevant evidence is made available. This information is neither intended nor implied to be a substitute for professional medical advice. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with questions regarding a medical condition.

Edits to original content made by Denver Health.