Myasthenia gravis (MG) can cause speech problems like slurring words or having trouble projecting your voice. These symptoms tend to get worse over time, even when other symptoms improve. They can also mask other health conditions, like stroke.

This guide explains why speech difficulties happen with MG, how you can improve communication without straining your voice, what treatment options you may have, and when to talk to your doctor.

What Types of Speech Problems Can Happen With Myasthenia Gravis?

People with MG may notice the following voice changes or speech problems:

• Slurring words
• Quickly losing your voice
• Speaking in a monotone
• Sounding more nasal than usual
• Developing a rough or hoarse voice
• Having a quieter voice
• Lacking voice projection

Slurred speech (known as dysarthria among healthcare professionals) is the most common speech problem among people with MG. It often comes with swallowing difficulties (known as dysphagia).

About 10 percent of people with MG will experience slurred speech. Other voice problems affect about 2 percent of people with MG.

Why Myasthenia Gravis Can Cause Speech Problems

A network of nerves sends messages to our muscles, telling them when and how to work. But when someone has myasthenia gravis, their body mistakenly destroys the part of the muscle that receives the nerves’ messages. This means certain muscles don’t always work as expected.

MG commonly affects the muscles needed for speech, such as those located in the throat, jaw, palate, tongue, or lips. When these muscles aren’t working right, someone with MG may not be able to make certain vowel or consonant sounds.

Tell your neurologist when you first notice speech problems, start to experience them more often, or think they’re getting worse.

People with MG also tend to experience muscle fatigue much faster than usual. Their speech muscles become more tired with every conversation, which can lead to worsening speech problems as the day goes on.

“When I start to get really tired, I have trouble getting words out. Not necessarily slurred, just trouble speaking,” said one MGteam member.

Another shared, “I often have slurred speech if I have been overly tired, and with MG that’s fairly often.”

How Speech Problems Affect People With Myasthenia Gravis

Being unable to speak as intended can feel frustrating. Others may have a hard time understanding what you’re saying. This can impact job performance, friendships, and daily life.

“[Weak] facial muscles, I can deal with that. But not being able to talk is the worst. Can’t talk over the phone,” one MGteam member shared.

People with MG have an increased risk of social isolation, loneliness, and anxiety. Speaking difficulties may play a role in this lower quality of life.

“I was isolated for the first six months of having MG,” another member shared. “I had double vision and couldn’t eat, talk, or swallow. It was painful to hold my head up. So, I had to be home.”

Treating Myasthenia Gravis Speech Problems

There are three main ways to treat speech difficulties associated with MG: rest, speech therapy, and medication.

1. Rest

MG-related muscle weakness often improves with rest. Periodically resting your voice throughout the day may help you avoid speech problems and vocal fatigue. During this time, you may need to rely on written communication or gestures.

2. Speech Therapy

A speech therapist (also known as a speech pathologist) can help you strengthen your speech muscles so they don’t tire quite so easily. They can also teach you strategies to use your speech muscles more intentionally and efficiently.

However, you may need to advocate for speech therapy. One study found more than half of all people with MG with problems speaking or swallowing weren’t offered voice evaluation or treatment.

“The one caregiver that provided the most support is a speech language pathologist,” one MGteam member said. “My tongue could go straight out or down but never up, until she used the electrical stimulation. All of this gave me such confidence and hope.”

3. Medication

Your healthcare provider may recommend MG medications to improve your symptoms and quality of life.

Slurred speech is the most common speech problem among people with MG. About 10 percent will experience it.

Some medications work by improving communication between the nerves and muscles, while others stop the body from mistakenly attacking itself. These treatments (and others) may reduce the likelihood of speech problems with MG.

MG medications may be taken daily as oral pills, while others are intravenous (IV) therapies administered by a healthcare professional every few weeks.

Treatment May Change Over Time

Evidence suggests that speech problems tend to worsen over time while other MG symptoms stabilize. It’s unclear why this happens. Talk to your doctor if your speech problems happen more often or become more severe. A different treatment approach may help.

Other Ways To Improve Communication

You may be able to reduce muscle fatigue and preserve your voice with these tips:

• Choose a quiet area for conversation so you don’t have to strain your voice to be heard.
• Request that others ask you yes or no questions whenever possible so you can answer with a nod or by shaking your head.
• Speak simply and directly to avoid having to repeat yourself.
• Make sure you have your listener’s full attention.
• Move your lips and tongue more when speaking to avoid overusing other muscles.
• Pronounce words clearly (enunciate).
• Breathe deeply and correctly to project your voice.
• Use gestures, facial expressions, and body language to help get your point across.

In some cases, MG can make it impossible to speak. “When I tried to talk, I couldn’t,” said one MGteam member. “They said [there were] no signs of stroke, but I didn’t talk for almost four months. Not a sound. No rhyme or reason.”

If this happens to you, consider using an assisted communication device. You can type a message and have the device speak it out loud. A speech therapist can help you learn about other types of communication technology.

“I often have slurred speech if I have been overly tired, and with MG that’s fairly often.”
— An MGteam member

It may also help to share your condition with others so they know why you’re having speech challenges. It’s up to you to disclose your diagnosis to others, and it’s a personal decision. But telling people about your MG may raise MG awareness and help others better understand what you’re facing.

When To Talk to Your Doctor

Tell your neurologist when you first notice speech problems, start to experience them more often, or think they’re getting worse. Also share whether your speech problems come with other symptoms, such as headaches, breathing difficulties, new movement challenges, or pain.

Other conditions can cause speech problems, so don’t assume that MG is the underlying cause. For instance, having MG may put you at a higher risk of experiencing thyroid problems. Thyroid issues may affect your speech.

Other conditions that could impact your speech include:

• Dementia
• Lyme disease
• Parkinson’s disease
• Stroke
• Traumatic injuries to the brain, face, mouth, or throat
• Certain types of cancer
• Vocal strain
• Cysts, polyps, or nodules on your vocal cords
• Chronic acid reflux
• Laryngitis
• Cerebral palsy
• Multiple sclerosis
• Muscular dystrophy
• Amyotrophic lateral sclerosis

One MGteam member shared how overlapping conditions can complicate diagnosis: “When I was diagnosed [with MG], I was being treated for sinus issues. My speech was terrible and swallowing was very difficult. What no one realized at the time was that the sinus drainage affected the muscles in my throat and caused the speech issue.”

Slurred speech could also be a side effect of some medications, including some anti-seizure medications, sedatives, and pain therapies.

When To Seek Emergency Care

MG can be life-threatening if your breathing muscles are affected. This is known as a myasthenic crisis and requires immediate medical attention. Watch for signs like difficulty talking, swallowing, and breathing.

“I went into MG crisis and had to be admitted to the intensive care unit. I couldn’t breathe, walk, or talk, I had chest pain, and my face looked like I had a stroke,” an MGteam member shared.

Join the Conversation

On MGteam, people share their experiences with myasthenia gravis, get advice, and find support from others who understand.

How have speech problems affected your life? Let others know in the comments below.