I can imagine cursed blood is not particularly palatable, though Astarion seems to enjoy the lyrium in my own.

[He was glad to be a regular source of nourishment for his lover. While he didn't particularly seek it out, he took pleasure from the act and the bite of his lover. He was glad to be available in such a way for his vhenan.]

Do you wish to see if your blood runs clean? It would be painful, but I would not wish for you to do so alone and risk yourself while your curse is lessened.