Hello from JA

Great question, thanks for coming to us.

You will have certain antibodies for life after having mono.

VCA IgG is present for life.

VCA IgM is present for about 6 weeks then disappears.

So to have VCA IgG is normal.
You do not have mono infection after 6 months, but you can still be weak from mono.

You need to find out if there are other reasons you are lethargic and here is what needs to be checked.

CBC...blood count, rule out anemia.
CMP..comprehensive metabolic panel which will show if your liver is ok, also sugars, kidneys, gallbladder, electrolytes.
Thyroid studies..this will make sure you are not hypothyroid and make sure your TSH is under 3.

Z pak has no place here unless you have a bacterial infection. Such as pneumonia, or urinary track infection.

I would stop all medicinal products unless you have a specific reason for them.

So that is a lot to throw at you

Let me know if you have further questions.

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