Medically Reviewed by Christopher B. Zust, MD

From an interview with Dr. Christopher Zust, McLeod Neurological Associates

Myasthenia gravis (MG) is a chronic autoimmune disease that affects the communication between nerves and muscles, leading to muscle weakness that can interfere with everyday activities. While there is currently no cure, advances in diagnosis and treatment have made it possible for many people with MG to lead active, fulfilling lives.

What Is Myasthenia Gravis?

Myasthenia gravis occurs when the body’s immune system mistakenly attacks the neuromuscular junction, the point where nerves communicate with muscles. Normally, nerves send signals that tell muscles to contract and move. In people with MG, this communication is disrupted, preventing those signals from reaching the muscles effectively.

Like other autoimmune conditions such as lupus and rheumatoid arthritis, MG is caused by the immune system attacking the body’s own tissues instead of protecting it from harmful bacteria and viruses.

Recognizing the Symptoms

Myasthenia gravis typically falls into one of two categories: ocular MG and generalized MG.

Ocular MG primarily affects the muscles that control the eyes. Common symptoms include drooping eyelids and double vision. These symptoms often fluctuate throughout the day, worsening with prolonged activities such as reading or watching television and improving after periods of rest.

Generalized MG includes the eye-related symptoms but also affects muscles throughout the body. People may experience weakness in their arms and legs, making it difficult to climb stairs or perform repetitive tasks. As with ocular symptoms, muscle weakness often becomes more noticeable with activity and improves with rest.

How Is Myasthenia Gravis Diagnosed?

For many patients, diagnosing myasthenia gravis begins with a simple blood test. Most people with MG have specific antibodies that can be detected in their bloodstream, providing strong evidence of the condition.

But, a small number of patients may not have detectable antibodies. In those cases, neurologists may recommend specialized nerve testing, including electromyography (EMG). This test measures how well nerves communicate with muscles by using small electrical stimulations and, in some cases, a fine needle that is placed into the muscle to record muscle activity.

Treatment Options

Although myasthenia gravis is not curable, it is highly treatable.

Treatment generally focuses on two approaches. The first involves what is referred to as a “nerve booster,” which are medications that improve communication between nerves and muscles. These medications help strengthen the signals traveling from nerves to muscles, reducing symptoms such as drooping eyelids, double vision, and muscle weakness. While they improve muscle function, they do not address the underlying autoimmune process.

The second approach targets the immune system itself. Immunosuppressive medications reduce the immune system’s attack on the neuromuscular junction, helping to decrease antibody activity. Prednisone is often the first medication used, although additional treatment options are available depending on each patient’s needs.

Because treatment must be carefully tailored to the individual, ongoing care from a neurologist, particularly one with specialized training in neuromuscular disorders, is often an important part of managing the disease.

Who Is Most at Risk?

Myasthenia gravis can affect people of any age, but certain groups are more commonly diagnosed. Women are affected approximately twice as often as men and are typically diagnosed at a younger age, often around 30 years old. Men are more likely to develop the condition later in life, usually in their 60s or 70s. But while these trends are common, MG can develop outside these age ranges as well.

Living with Myasthenia Gravis

Receiving a diagnosis of myasthenia gravis can feel overwhelming, but the outlook for many patients is encouraging. Although the condition requires lifelong management, many patients live a very happy, productive, and normal life.