What decides which way to go ( injection vs pills) with multiple sclerosis? and which one is better? injections or pills?

Difficult question: You have some medical issues that would require a very careful investigation into the risk and potential benefits of taking medications that modify your immune system. I would have a sit down discussion with a trusted neurologist who can review your history in detail and give you informed advice.

EACH PT DIFFERENT: Generic answer: in most cases, injections of interferons are being phased out, but copaxone, spec. In tiw form widely used. Aubagio, tecfidera, gilenya, increasingly used due to lack of needles. But the two most potent drugs are tysabri (natalizumab) and gilenya. Risk and safety are issues here. At age 82, not sure you need an ms med. Get opinion from ms neurologist.