Oh, I understand your concern now. Plavix causes prolonged bleeding. If you have had anal sex before and did not have any bleeding before, I don't see why you can't have it now. Just use any and all precautions to make it is safe as possible (lots of lubrication, relaxation of the sphincter, gentleness by your partner...)
Keep in mind that any cuts or tears in the anus are slow to heal. Prolonged bleeding will slow this process down even further.
Hope this helps.
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