Myasthenia gravis (MG) is an autoimmune neuromuscular disease that affects the muscles in the body. It's a chronic disease that causes certain muscles to become very weak when they are being used for a period of time. The muscles usually return to normal strength after the muscles have a chance to rest.
The first signs of myasthenia gravis are usually slurred speech, problems swallowing, and weakness of the muscles around the eyes ("ocular MG"). Weakness in facial muscles can cause loss of eye control and eyelid movement, drooping of one eye, double vision, decreased ability to make facial expressions, and problems talking and chewing properly ("bulbar-onset MG").
Muscle weakness in the neck and chest caused by MG can result in difficulty swallowing, breathing, speaking, and neck weakness. Other parts of the body that usually experience weakness include arms, hands, fingers, and legs.
In some instances, people with MG can experience "myasthenic crisis." This occurs when the respiratory muscles become paralyzed, requiring individuals to be put on breathing machines.
Myasthenia can be fairly mild and controlled with medication or it can progress quickly to a disabling state. When myasthenia gravis begins to affect your muscles so much that you can no longer work, there are two ways that Social Security might approve you for SSDI or SSI benefits.
First, you could meet the requirements of the disability listing for myasthenia gravis, for automatic approval. Second, Social Security could agree that MG is affecting your muscle function so much that you can no longer do "substantial gainful activity," or "SGA." (SGA generally means work that earns you more than about $1,500 per month.)
With either method, you need to show that your symptoms have continued after you took medication as prescribed by your doctor, or followed other prescribed treatment procedures, for at least three consecutive months.
Myasthenia gravis has its own disability listing in the Social Security listing of impairments that can qualify for disability. To prove you meet the requirements of the MG listing, listing 11.12, you must have a diagnosis of myasthenia gravis and prove that you have one of the following:
Proving MG can be difficult because, when patients' muscles are at rest, they don't generally have significant noted weakness; it's only after use that they become fatigued. For instance, in patients with bulbar-onset MG, the muscles used for chewing often become fatigued halfway through a meal. For this reason, it's important that your doctor brings your muscles to fatigue during testing and records the progressive weakness of your muscles.
To fulfill the requirements of the listing, your medical records should include evidence such as
In addition, some patients with MG have lengthy periods of remission, with very few symptoms, followed by exacerbations, with great muscle fatigue. But Social Security is aware that MG can be episodic, so it will consider the frequency and duration of exacerbations and how long periods of remission last.
Some patients with myasthenia gravis won't meet the criteria in the above listing because they don't have problems swallowing, breathing, talking, or walking, or their doctor hasn't recorded a level of weakness in their arms or legs that Social Security considers severe enough. These patients may nevertheless have limitations that prevent them from successfully returning to work and being able to work enough to earn $1,500 per month.
If you don't "meet the listing," Social Security will review your medical record for limitations that your doctor has documented and will gather them into a Residual Functional Capacity (RFC) assessment. Your RFC shows which work activities and jobs you have the ability to do, if any.
Due to muscle fatigue in the legs and/or arms, MG can limit any type of physical activity. Specifically, if you have weakness in your legs, walking or standing for long periods of time is difficult, which would limit you to sedentary (sit-down) work. Weakness in your arms, hands, or fingers makes completing tasks using your fingers difficult, which could rule out any sedentary work, or at least would rule out light or medium work that requires lifting or carrying items.
If MG has affected your eyesight or your speech, this rules out many jobs that require good vision or communication, such as working with machinery, driving, working with the public, and so on.
With MG, patients can often do some work, but need frequent rest breaks due to their easy fatigability. If you can complete some tasks required by a job, but your productivity is decreased by 20% or more due to your MG, Social Security is supposed to grant you disability benefits on that fact alone.
You should record how easily your muscles are fatigued by keeping an activity diary, where you take notes on how many minutes of an activity, including speaking, weakens your muscles, and submit it to Social Security with your application or appeal. (For more information, see our article on qualifying for disability due to reduced productivity.)
After your RFC assessment, Social Security decides whether, given the work activities that your RFC says you're limited to doing, there are any jobs you can be expected to do, also taking into account your job experience, education, and age. For information on how the agency makes this decision, see our article on how Social Security uses the RFC to decide if you can work.
If you're applying for Social Security disability insurance (SSDI), you can file your whole claim online on Social Security's website. Most individuals filing for SSI only can't file the entire application online, but they can get started on Social Security's website.
If you're not comfortable online, call Social Security at 800-772-1213 to start your claim. You might also be able to contact your local field office for an in-person appointment (use the Social Security field office locator and enter your zip code to find your local field office). For more information on applying for either SSDI or SSI, see our article on applying for Social Security disability benefits.
If you'd like help with your application, think about working with an SSDI expert. According to a survey of our readers, applicants who filed an initial application without expert help were denied 80% of the time.
Updated December 30, 2022