Dysarthria

Date Updated: 05/17/2022

Overview

Dysarthria 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.

Symptoms

Signs 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 doctor

Dysarthria can be a sign of a serious condition. See your doctor if you have sudden or unexplained changes in your ability to speak.

Causes

In 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.

Complications

Because 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.

Diagnosis

A speech-language pathologist might evaluate your speech to help determine the type of dysarthria you have. This can be helpful to the neurologist, who will look for the underlying cause.

Besides conducting a physical exam, your doctor might order tests to identify underlying conditions, including:

Imaging tests. Imaging tests, such as an MRI or CT scan, create detailed images of your brain, head and neck that may help identify the cause of your speech problem.
Brain and nerve studies. These can help pinpoint the source of your symptoms. An electroencephalogram (EEG) measures electrical activity in your brain. An electromyogram (EMG) evaluates electrical activity in your nerves as they transmit messages to your muscles. Nerve conduction studies measure the strength and speed of the electrical signals as they travel through your nerves to your muscles.
Blood and urine tests. These can help determine if an infectious or inflammatory disease is causing your symptoms.
Lumbar puncture (spinal tap). In this procedure, a doctor or nurse inserts a needle in your lower back to remove a small sample of cerebrospinal fluid for laboratory testing. A lumbar puncture can help diagnose serious infections, disorders of the central nervous system, and cancers of the brain or spinal cord.
Brain biopsy. If a brain tumor is suspected, your doctor may remove a small sample of your brain tissue to test.
Neuropsychological tests. These measure your thinking (cognitive) skills, your ability to understand speech, your ability to understand reading and writing, and other skills. Dysarthria doesn't affect your cognitive skills and understanding of speech and writing, but an underlying condition can.

Treatment

Your treatment will depend on the cause and severity of your symptoms and the type of dysarthria you have.

Your doctor will treat the cause of your dysarthria when possible, which may improve your speech. If your dysarthria is caused by prescription medications, talk to your doctor about changing or stopping such medications.

Speech and language therapy

You may have speech and language therapy to help you regain normal speech and improve communication. Your speech therapy goals might include adjusting speech rate, strengthening muscles, increasing breath support, improving articulation and helping family members communicate with you.

Your speech-language pathologist may recommend trying other communication methods if speech and language therapy isn't effective. These communication methods could include visual cues, gestures, an alphabet board or computer-based technology.

Coping and support

If you have significant dysarthria that makes your speech difficult to understand, these suggestions may help you communicate more effectively:

Speak slowly. Listeners may understand you better with additional time to think about what they're hearing.
Start small. Introduce your topic with one word or a short phrase before speaking in longer sentences.
Gauge understanding. Ask listeners to confirm that they know what you're saying.
If you're tired, keep it short. Fatigue can make your speech more difficult to understand.
Have a backup. Writing messages can be helpful. Type messages on a cellphone or hand-held device, or carry a pencil and small pad of paper with you.
Use shortcuts. Create drawings and diagrams or use photos during conversations, so you don't have to say everything. Gesturing or pointing to an object also can help convey your message.

Family and friends

If you have a family member or friend with dysarthria, the following suggestions may help you better communicate with that person:

Allow the person time to talk.
Don't finish sentences or correct errors.
Look at the person when he or she is speaking.
Reduce distracting noises in the environment.
Ask yes or no questions.
Tell the person if you're having trouble understanding.
Keep paper and pencils or pens readily available.
Help the person with dysarthria create a book of words, pictures and photos to assist with conversations.
Involve the person with dysarthria in conversations as much as possible.
Talk normally. Many people with dysarthria understand others without difficulty, so there's no need to slow down or speak loudly when you talk.

Preparing for an appointment

Dysarthria requires prompt medical attention. See a doctor right away if you have sudden or unexplained changes in your ability to speak.

If the changes are more subtle, you'll likely start by seeing your primary care doctor. If your doctor suspects a medical condition is causing your symptoms, he or she will likely refer you to a nervous system specialist (neurologist) for further evaluation.

Here's what you can do to get ready for your appointment.

Be aware of pre-appointment restrictions. Ask if there's anything you need to do in advance, such as restrict your diet for blood tests.
Write down your symptoms, including any that may seem unrelated to the reason for which you scheduled the appointment.
Write down key personal information, including major stresses or recent life changes.
List all medications, vitamins and supplements you take.
Take a family member or friend along, if possible. Someone who accompanies you can help you remember information.
Write down questions to ask your doctor.

For dysarthria, some basic questions to ask your doctor include:

What's the most likely cause of my symptoms?
What tests do I need?
Will I need to see a specialist?
What treatments are available?
Are there brochures or other printed material that I can have? What websites do you recommend?

Don't hesitate to ask other questions, as well.

What to expect from your doctor

Your doctor is likely to ask you a number of questions, including:

When did your symptoms begin?
Have your symptoms been continuous or occasional?
How severe are your symptoms?
Does anything seem to improve your symptoms?
What, if anything, appears to worsen your symptoms?