I suggest you call your surgeon's office and ask the nurse or PA. Generally, whenever someone has scalp incisions, we recommend they wait until the incisions are fully healed, staples/sutures removed, and so on before they apply any hair color. You want to make sure you don't have any openings in the skin when you apply the colorant because this could be irritating or lead to infection.
So, again, best bet is to call your surgeon's office and ask. They can give you specific information.
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