Melissa,

I'd love to be able to give you a concrete answer, but only his doctor can do that. How severe these blood clots are depends on many factors including size, location, and other issues. Sometimes, clots can cause strokes. Your father definitely has big risk factors, the heavy drinking and smoking issues you mentioned.

Sorry, but the best advice I can give you is to gave a talk with your dad's doctor.

This has to be very frightening for you. If you'd like some additional support, come join our discussion forum. You'll need to register again once there because it's a separate membership database, but you can use the same member name, email address, and password that you used here. You can find our forum at http://forums.healthcentral.com/discussion/migraine/forums.

Good luck,

Teri