I don't understand why this is a concern. Assuming you are a woman, if you are healthy enough for regular vaginal intercourse while on Plavix, you are healthy enough for anal sex. I am also assuming that your doctor has told you whether or not your heart is strong enough for sexual activity. If your doc has not told you, then you need to clear it with him or her before you engage in any sexual activity while on this drug.
I have been told that the anus is more vascular and may have a greater risk for bleeding (although this has not been a problem in the past). I have not been able to locate any literature, research or other information to confirm or dispute this.
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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