Understanding Myasthenia Gravis - Treatment

How Do I Know If I Have Myasthenia Gravis?

During a physical examination, your healthcare provider may observe signs such as a droopy eyelid, difficulty holding your arms out at shoulder length for a reasonable length of time, or a weak grasp. Blood tests may reveal the presence of acetylcholine-receptor antibodies. Specialized tests use electricity to stimulate muscles, and at the same time, measure the strength of muscle contraction.

If you have myasthenia gravis, muscle strength will decrease predictably over the course of testing. You may be given certain medications -- edrophonium or neostigmine -- as part of a diagnostic examination. In a patient with myasthenia gravis, these medications will significantly and noticeably improve muscle strength for a short time. This helps to further confirm the diagnosis.

Because other conditions sometimes occur along with myasthenia gravis and can interfere with treatment, your healthcare provider may order other tests. You may need a CT scan or an MRI to check for a thymoma. You'll be checked for high blood pressure and glaucoma, and you'll probably have your blood tested to see if you have thyroid disease, other autoimmune diseases (such as rheumatoid arthritis or systemic lupus erythematosus), diabetes, kidney problems, or any infections.

What Are the Treatments for Myasthenia Gravis?

There is no cure for myasthenia gravis, but it is treated with medications and sometimes surgery. You may be put on a medication called pyridostigmine, that increases the amount of acetylcholine available to stimulate the receptors. Prednisone and other immunosuppressant drugs, like azathioprine, cyclosporine, or cyclophosphamide, may be given to slow down the production of anti-acetylcholine antibodies.

Research is under way to determine if another immunosuppressant, mycophenolate mofetil (CellCept), is as effective. Initial results look promising and show it to be effective and to have fewer side effects than do azathioprine and cyclosporine.

In severe cases, you may need to have your blood sent through a special machine that removes the antibody-containing plasma and replaces it with antibody-free plasma. This is called plasmapheresis. You may also be given a preparation called immunoglobulin through a needle in a vein.

If you have a thymoma, you will need surgery to remove your thymus. In fact, your doctor may recommend that you undergo this surgery even if no tumor is present because removal of the thymus seems to improve symptoms in many patients.

If you begin to have difficulty breathing due to weakness of the respiratory muscles, you may need to be admitted to the hospital intensive care unit and placed temporarily on a respirator. Myasthenic crisis often occurs when you develop a severe infection, so you'll probably need to be treated with antibiotics as well.

Situations that affect myasthenia gravis include:

• Changes in thyroid function
• Surgery
• Radiation therapy
• Infection

Certain medications can exacerbate symptoms of myasthenia gravis, including:

• Antibiotics (particularly those called aminoglycosides)
• Narcotic medicines
• Penicillamine
• Magnesium
• Anesthetic agents
• Muscle relaxants
• Some drugs used to treat heart arrhythmias

Some women notice that their symptoms worsen around the time of their menstrual period. Pregnancy's effect on myasthenia gravis is unpredictable. About one-third of all women have an improvement in their symptoms, one-third have no change, and one-third suffer an exacerbation.

How Can I Prevent Myasthenia Gravis?

There are no known ways to prevent myasthenia gravis. If you already have the condition, take these steps to avoid an exacerbation:

• Try to prevent infections by careful hygiene and avoiding sick people.
• Treat infections promptly.
• Do not become overheated or too chilled.
• Avoid overexertion.
• Learn effective methods of dealing with stress in your life.