When do you initiate immunosuppressant drugs for patients with a diagnosis of myasthenia gravis?

I assume the question refers to non-steroid immunosuppressant drugs such as azathioprine, mycophenolate, methotrexate, etc. I use those drugs predominantly in generalized MG (although a few patients with ocular MG may also require them), a) in any patient that requires prednisone doses of >20 mg dai...