Edrophonium test
If it’s still not clear what’s causing your symptoms, your doctor may suggest a test called an edrophonium test. It involves getting an injection of a medicine called edrophonium chloride. If you have a sudden but temporary improvement in muscle strength after the injection, it’s likely you have myasthenia gravis. But this test is rarely done these days because there’s a risk it could lead to potentially severe side effects, such as a slow heartbeat and breathing problems [4]. It’s only done if absolutely necessary and in a hospital setting where treatment for any side effects is readily available.