Nosebleeds are very common. Most nosebleeds occur because of minor irritations or colds. They can be frightening for some patients, but are rarely life threatening.
The nose contains many small blood vessels that bleed easily. Air moving through the nose can dry and irritate the membranes lining the inside of the nose, forming crusts. These crusts bleed when irritated by rubbing, picking, or blowing the nose.
The lining of the nose is more likely to become dry and irritated from low humidity, allergies, colds, or sinusitis. Thus, nosebleeds occur more frequently in the winter when viruses are common and heated indoor air dries out the nostrils. A deviated septum, foreign object in the nose, or other nasal blockage can also cause a nosebleed.
Most nosebleeds occur on the front of the nasal septum, the tissue that separates the two sides of the nose. The septum contains many fragile, easily damaged blood vessels. This type of nosebleed can be easy for a trained professional to stop. Less commonly, nosebleeds may occur higher on the septum or deeper in the nose. Such nosebleeds may be harder to control.
Occasionally, nosebleeds may indicate other disorders such as bleeding disorders or high blood pressure.
Frequent nosebleeds may also be a sign of hereditary hemorrhagic telangiectasia (also called HHT or Osler-Weber-Rendu syndrome).
Blood thinners such as Coumadin, Plavix, or aspirin may cause or worsen nosebleeds.