Doctors use a variety of treatments, alone or in combination, to relieve symptoms of myasthenia gravis.
Cholinesterase inhibitors. Medications such as pyridostigmine (Mestinon) enhance communication between nerves and muscles. These medications don't cure the underlying condition, but they may improve muscle contraction and muscle strength.
Possible side effects may include gastrointestinal upset, nausea, and excessive salivation and sweating.
Corticosteroids. Corticosteroids such as prednisone inhibit the immune system, limiting antibody production.
Prolonged use of corticosteroids, however, can lead to serious side effects, such as bone thinning, weight gain, diabetes and increased risk of some infections.
Immunosuppressants. Your doctor may also prescribe other medications that alter your immune system, such as azathioprine (Imuran), mycophenolate mofetil (CellCept), cyclosporine (Sandimmune, Neoral), methotrexate (Trexall) or tacrolimus (Prograf).
Side effects of immunosuppressants can be serious and may include nausea, vomiting, gastrointestinal upset, increased risk of infection, liver damage and kidney damage.
Plasmapheresis (plaz-muh-fuh-REE-sis). This procedure uses a filtering process similar to dialysis. Your blood is routed through a machine that removes the antibodies that block transmission of signals from your nerve endings to your muscles' receptor sites. However, the beneficial effects usually last only a few weeks.
After repeated treatments, it may be difficult for doctors to gain access to your vein. They may need to implant a long, flexible tube (catheter) into your chest to conduct the procedure.
Other risks associated with plasmapheresis include a drop in blood pressure, bleeding, heart rhythm problems or muscle cramps. Some people may also develop an allergic reaction to the solutions used to replace the plasma.
Intravenous immunoglobulin (IVIg). This therapy provides your body with normal antibodies, which alters your immune system response.
IVIg has a lower risk of side effects than do plasmapheresis and immune-suppressing therapy. However, it may take about a week to start working, and the benefits usually last no more than three to six weeks.
Side effects, which usually are mild, may include chills, dizziness, headaches and fluid retention.
Monoclonal antibody. Rituximab (Rituxan) is an intravenous medication that is used in some cases of myasthenia gravis. This drug depletes certain white blood cells, altering the immune system and improving myasthenia gravis.
Rituximab is usually given in infusions at an infusion center or done in a hospital on an outpatient basis. Repeat infusions are often done over a few weeks. Occasionally the infusions are repeated months later.
About 15 percent of the people with myasthenia gravis have a tumor in their thymus gland, a gland under the breastbone that is involved with the immune system. If you have a tumor, called a thymoma, doctors will conduct surgery to remove your thymus gland (thymectomy).
If you don't have a tumor in the thymus gland, surgery to remove the thymus gland may improve your myasthenia gravis symptoms. It may eliminate your symptoms, and you may be able to stop taking medications for your condition. However, you may not notice the benefits of a thymectomy for several years, if at all.
A thymectomy may be performed as an open surgery or as a minimally invasive surgery.
In an open surgery, your surgeon splits the central breast bone (sternum) to open your chest and remove your thymus gland.
Surgeons may perform minimally invasive surgery to remove the thymus gland, which uses smaller incisions. Minimally invasive thymectomy may include:
Video-assisted thymectomy. In one form of this surgery, surgeons make a small incision in your neck and use a long thin camera (video endoscope) and small instruments to visualize and remove the thymus gland through your neck.
Alternatively, surgeons may make a few small incisions in the side of your chest. Doctors use a video scope and small instruments to conduct the procedure and remove the thymus gland through these incisions.
- Robot-assisted thymectomy. In a robot-assisted thymectomy, surgeons make several small incisions in the side of your chest. Surgeons conduct the procedure to remove the thymus gland using a robotic system, which includes a camera arm and mechanical arms.
Benefits of these procedures may include less blood loss, less pain, lower mortality rates and shorter hospital stays compared with open surgery.
Your doctor will determine which treatment may be most appropriate for you based on several factors, including:
- Your age
- Severity of your condition
- Location of muscles affected
- Other existing medical conditions
April 23, 2016
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