Reasons For A Nose Bleed

The nose warms and humidifies inhaled air, which keeps the membranes that line the inside of the nose moist. Many blood vessels lie close to the surface inside the nose and a nosebleed can occur from minor irritations to the lining. Nosebleeds happen at any age and most people will develop a nosebleed in their lifetime, according to the American Academy of Otolaryngology.

Dry Air

The very cold or dry, heated, indoor air that dominates many people's environment during the winter months moves through the nose, drying and irritating the membranes lining the inside of the nose, causing a nosebleed when rubbed or picked. Dry, hot air that occurs in low-humidity climates can dry out the mucus membranes, leaving them more susceptible to bleeding as well, according to the Cleveland Clinic.

Infections

Colds, upper respiratory infections, and sinusitis--especially episodes that cause repeated sneezing, coughing, and vigorous nose blowing--irritate the lining of the nose and cause a nosebleed by rupturing the superficial blood vessels inside the nose, according to the Cleveland clinic.

Allergies

Nosebleeds occur from allergies affecting the nose, by causing inflammation, irritation, dryness of the nasal lining and itching--which leads to nose-picking, according to the American Academy of Otolaryngology.

Injury to the Nose

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. A deviated septum or an abnormal shape of the structure can occur from any direct injury to the nose, such as seen in a broken nose. Seek emergency care from a trained, medical professional when a nosebleed occurs from an injury, because head injuries that result in nosebleeds may indicate a more serious underlying problem, according to Medline Plus.

Foreign Object

The insertion of a foreign object into the nose irritates and damages the lining of the nose, resulting in a nosebleed, according to Medline Plus.

Medications

Taking large doses of an ant-inflammatory, such as ibuprofen and blood-thinning medications, including aspirin, may cause or worsen nosebleeds, according to the Cleveland Clinic.

Chemical Irritants

Chemical irritants including illegal drugs--particularly cocaine usage, industrial chemicals and an overuse of nasal sprays, irritate the nasal lining and cause nosebleeds, according to the Cleveland Clinic.

Certain Disorders

Nosebleeds that occur frequently may indicate certain disorders such as a bleeding disorder and high blood pressure. Frequent nosebleeds also occur in a hereditary disorder called hereditary hemorrhagic telangiectasia, also known as HHT. Characteristics of HHT involve a blood vessel-type growth similar to a birthmark in the back of the nose. The American Academy of Otolaryngology recommends a thorough examination by an ear, nose, and throat specialist or an ENT, if frequent unexplainable nosebleeds occur.

Tumors

Tumors of the nose and sinuses, either malignant or nonmalignant, cause repeated nosebleeds--particularly in the older individual and in smokers, according to the American Academy of Otolaryngology.

Livestrong.com