Answer:
Nosebleeds occur when the moist inner lining of the nose is irritated or when blood vessels in the nose are broken. There are many causes of nosebleeds. In all cases, people who take aspirin or other drugs that interfere with blood clotting (anticoagulants), people with clotting disorders, and people with hardening of the arteries (arteriosclerosis) are more likely to develop nosebleeds.
Common causes
The most common causes of nosebleeds are
Trauma (such as nose blowing and picking)
Drying of the moist inner lining of the nose (such as occurs in winter)
Less common causes
Less common causes of nosebleeds include
Nasal infections
Foreign objects
Rendu-Osler-Weber syndrome
Tumors of the nose or sinuses
Bleeding disorders (coagulopathies)
Bodywide (systemic) disorders
High blood pressure (hypertension) may help keep a nosebleed going that has already begun but is unlikely to be the actual cause.
