Is it safe to donate plasma post weeks later after FUT transplant?

Donating blood or plasma should not affect your surgery.  If you are concerned it is always a good idea to contact your doctor.

It is fine to donate blood any time after a hair transplant.The only contraindication would be if you are on Propecia.

It is my belief that the scar that you will have from strip procedure really depends significantly on scalp exercise prior to the procedure and the techniques used during the procedure. Although, Plasma may contribute to some better wound healing I would actually not recommend doing it after the procedure. At this time, it may not make much any difference. I would not to do it.

This is a question you need to ask the agency that will take your donation. They will usually tell you the answer to that question.