Honestly? I have no idea. This was Ciri's theory in the first place.

[It made sense, of course. Alucard's blood always had healing properties. His bones now had weird magic that focused on rebuilding and adding structure. To think that finding a way to consume them might help was perfectly logical, if not a little unnerving. It spoke to how dire the situation felt from her perspective, and as unsure as Alucard was about how it all might go, it seemed a small thing to give a friend.

He sighs, leaning against the counter in the middle of the woods once Geralt's taken the mug.]

Maybe just take a sip or two first and then see what happens. Chugging this seems ill advised at best.