Disability Benefits for Myasthenia Gravis

How SSA Evaluates Myasthenia Gravis Under Listing 11.12

Myasthenia gravis is an autoimmune disease that disrupts the signal between nerves and muscles, causing muscle weakness that worsens with activity and improves with rest. It often affects the eyes, face, throat, and limbs. SSA evaluates it under Blue Book listing 11.12, which can be met in one of two ways, both requiring that the problem persist despite at least three months of prescribed treatment.

• 11.12A — bulbar and breathing symptoms. Significant and persistent difficulty with speaking, swallowing, or breathing (the muscles controlled by the bulbar nerves).
• 11.12B — limb weakness. Significant and persistent disorganization of motor function in two extremities, causing an extreme limitation in standing up from a seated position, balancing, or using the arms.

A third path applies when there is a marked limitation in physical functioning together with a marked limitation in one area of mental functioning, such as concentrating and keeping pace or managing yourself. Because myasthenia gravis fluctuates — symptoms come and go and worsen as the day goes on — SSA looks at the pattern over time rather than a single exam. Severe flares, called myasthenic crises, can affect breathing and require hospitalization, and documenting these episodes strengthens a claim. The variable, fatigue-driven nature of the weakness is central to how SSA understands the disease.

Medical Evidence for a Myasthenia Gravis Claim

Because the weakness fluctuates, a consistent record over time matters most. SSA will look for:

• Diagnostic testing — acetylcholine receptor or MuSK antibody blood tests, repetitive nerve stimulation, or single-fiber EMG.
• Exam findings — documented weakness of the eyes, face, throat, or limbs, and how it worsens with sustained effort.
• Records of speech, swallowing, and breathing problems, including any myasthenic crises or hospitalizations.
• Treatment history — medications, immunotherapy, plasma exchange, or thymus surgery, and your response.

Ask your neurologist to describe how weakness and fatigue change over the course of a day and how they limit activity, speech, and swallowing. Because symptoms improve with rest and worsen with use, evidence showing that you cannot sustain activity across a full day — not just at a single moment — is what makes a myasthenia gravis claim persuasive.

Qualifying Through an RFC Assessment

When myasthenia gravis does not meet listing 11.12, SSA assesses residual functional capacity (RFC). The defining feature is fatigable weakness: strength that may be adequate at rest but drops quickly with repeated use. This limits sustained standing, walking, lifting, and repetitive hand use, and can affect vision through drooping eyelids or double vision. Weakness of the throat muscles can make prolonged talking difficult.

Because symptoms worsen as the day goes on and flare unpredictably, many people cannot maintain the steady pace and reliable attendance that full-time work requires, and heat, stress, or illness can trigger a setback. SSA builds these limits into an RFC that may include reduced exertion, extra rest breaks, and limits on sustained activity. It then compares that RFC to your past work. If you cannot sustain it, the medical-vocational grid rules may direct a finding of disabled, especially for claimants age 50 and older.

Tips for a Stronger Myasthenia Gravis Claim

• Emphasize fatigability. Explain that your strength fades with repeated use, since single-moment strength testing can look normal.
• Document crises and hospital stays for breathing or swallowing problems, which show the severity of the disease.
• Track your day. Note how symptoms worsen from morning to evening so SSA sees you cannot sustain activity.
• Report vision, speech, and swallowing problems, not just limb weakness.
• Stay in neurology care and keep testing and treatment records complete and current.