Complications of myasthenia gravis are treatable, but some can be life-threatening.

Myasthenic crisis

Myasthenic crisis is a life-threatening condition that occurs when the muscles that control breathing become too weak to do their jobs. Emergency treatment is needed to provide mechanical assistance with breathing. Medications and blood-filtering therapies help people to again breathe on their own.

Thymus tumors

About 15 percent of people with myasthenia gravis have a tumor in their thymus, a gland under the breastbone that is involved with the immune system. Most of these tumors, called thymomas, aren't cancerous (malignant).

Other disorders

People with myasthenia gravis are more likely to have the following conditions:

  • Underactive or overactive thyroid. The thyroid gland, which is in the neck, secretes hormones that regulate your metabolism. If your thyroid is underactive, you may have difficulties dealing with cold, weight gain and other issues. An overactive thyroid can cause difficulties dealing with heat, weight loss and other issues.
  • Autoimmune conditions. People with myasthenia gravis may be more likely to have autoimmune conditions, such as rheumatoid arthritis or lupus.
Apr. 23, 2013

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