Brief Answer:
Most patients do not need have any major limitations.

Detailed Answer:
I read your question carefully and I understand your concern.

The answer depends also on the form, the classification grade of myasthenia. About 10% of patients have only ocular myasthenia which doesn't cause particular restrictions, others have other grades with more severe symptoms involving swallowing and breathing difficulties. So impact on life depends on grade.

Generally most patients are able to perform most of their activities, he can do all what you mention in your query. The main limitation is fatigue which will limit his ability to perform intensive exercise or physical work. That doesn't mean he should rest without doing anything, light exercise and daily activities are encouraged, no major limitations, should do all what he can afford to without exhausting himself.
Should have a healthy Mediterranean diet and avoid gaining weight as much as possible (that applies to all of us actually, but even more so in myasthenic patients).

Apart from limitations caused by the disease itself there may be side effects of therapy. In particular that applies to the case when corticosteroid treatment is necessary which in itself can lead to weight gain, retaining fluids, stomach ulcers, high blood pressure etc.

One other limitation is in case he needs treatment for some other conditions (say antibiotics) there are many medications which when possible should be avoided in myasthenic patients as they can worsen myasthenia. For that reason extra care should be paid to avoiding infections, in particular respiratory infections which are also influenced by the respiratory muscle weakness due to myasthenia. The list of such drugs is long, doesn't mean that they are never to be used, some may be used, but only when strictly necessary.

I remain at your disposal for other questions.

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