What are the symptoms of phlebitis?

Inflammation: Phlebitis is an itis (inflammation) of a phleb (vein). We usually think of phlebitis as being a problem involving a clot in a superficial vein. Typically the symptoms are those of inflammation and include pain, swelling, warmth, and redness. The pain is often very localized. Even though superficial, it is important to make sure that the clot doesn't even into a deep vein with ultrasound.