The acetylcholine receptor antibody attacks receptors for the neurotransmitter acetylcholine, which sends signals from nerves to muscles and from nerve to nerve in the brain. The antibody prevents transmission of the signal and causes muscle weakness.

Acetylcholine receptor antibody testing can confirm a diagnosis of myasthenia gravis for those suspected of having this disease.

Symptoms include weakness that gets worse as they day progresses or with repeated exertion, blurred or double vision, nasal-sounding voice and difficulty swallowing.

Other tests to diagnose myasthenia gravis include single-fiber EMG which shows a particular pattern in myasthenia gravis and an edrophonium challenge. The edrophonium challenge is done by injecting this drug intravenously and looking to see if there is improvement in strength by objective testing. Though no one test is specific and sensitive to make the diagnosis of myasthenia, if they are positive, it is likely that this is the correct diagnosis.

While some people have a generally benign course, myasthenia gravis can be life threatening during "crises." This occurs when respiratory muscles become weak and breathing becomes difficult. Use of a respirator is then necessary to support breathing through the crisis and until medications and treatments can take effect.

If symptoms of weakness, blurry or double vision, or change in voice occur, see your healthcare professional.