The Medical Consumer's Advocate
Q: 
My father in law has been
experiencing nose bleeds. My concern is that they are not
anterior nosebleeds; they begin in the back of the nose,
sometimes only flowing down the throat. After the last
nose bleed he had, the following day he had dizziness and
lightheadedness. The nose bleeds can come on with no
warning, i.e., sitting down watching TV, or
during physical activity, i.e., playing with a 4
yr old grandchild. I just need to know if these symptoms
are something to really worry about? Thank you.
A: Yes, this is something to worry about.
Posterior bleeds are usually found in people with high blood
pressure, and/or small vessel disease (diabetes, for example,
is an illness which causes problems with small blood
vessels). Atherosclerosis ("hardening of the
arteries") is another illness that can contribute to
posterior nose bleeds. One reason to see a doctor is to
determine whether he has any of these underlying illnesses,
which are serious in their own right.
Posterior nosebleeds are more difficult to control than
anterior nosebleeds. You can't just pinch your nose -- you
have to depend on your natural clotting mechanisms to do the
job. Consequently, blood loss can, at times, be severe and
even life-threatening. Your father-in-law's bout of dizziness
and lightheadedness suggests that his blood loss may have
been severe.
Finally, posterior nosebleeds can be symptoms of other
rare, life-threatening problems, such as tumors or
arteriovenous malformations. Do whatever you can to convince
him to see an ear, nose, and throat specialist. It is not an
exaggeration to say that his life is in danger.