[quote=tgulick]bleeding terribly from his right nostril. He has been very excited lately over my Sheltie being in heat. His bleeding started last night. What could be wrong?[/quote]
Epistaxis (bleeding nose) can be a serious symptom, or (as with many children) it may be nothing at all. If your dog is older and has any other warning signs of systemic illness you should get a complete work-up at your vet’s.
Clotting disorders (especially secondary to toxic exposure like anticoagulant rodenticides), thrombocytopenia (low platelet count) e.g. from Ehrlichia (a tick-borne disease), and infiltrative disease are among the most common uinderlying problems. That’s assuming that it’s not just something silly like hitting his nose due to the excitement due to your Sheltie’s estrous.
I imagine that you may have already gone to the vet or stopped the bleeding on your own. In general though the best acute care for a nose bleed is presssure and cold. Pack the nose with ice cold tissues or ice chips. Try to keep his head elevated. Of course with bad, unrelenting bleeding your best bet is to get right to a 24 hour emergency clinic.
Good luck. Let us know what your vet finds (if you bring him in).