What causes nosebleeds?
The purpose of the nose is to warm and humidify the air that we breathe in. The nose is lined with many blood vessels that lie close to the surface where they can be injured and bleed. Once a vessel starts to bleed, the bleeding tends to recur since the clot or scab is easily dislodged. Nosebleeds, called epistaxis, can be messy and even scary, but often look worse than they are. Many can be treated at home, but some do require medical care.
Common causes of nosebleeds include:
- Dry, heated, indoor air, which dries out the nasal membranes and causes them to become cracked or crusted and bleed when rubbed or picked or when blowing the nose (more common in winter months)
- Dry, hot, low-humidity climates, which can dry out the mucus membranes
- Colds (upper respiratory infections) and sinusitis, especially episodes that cause repeated sneezing, coughing, and nose blowing
- Vigorous nose blowing or nose picking
- The insertion of a foreign object into the nose
- Injury to the nose and/or face
- Allergic and non-allergic rhinitis (inflammation of the nasal lining)
- Use of drugs that thin the blood (aspirin, non-steroidal anti-inflammatory medications, warfarin, and others)
- High blood pressure
- Chemical irritants (e.g., cocaine, industrial chemicals, others)
- Deviated septum (an abnormal shape of the structure that separates the two sides of the nose)
- Tumors or inherited bleeding disorders (rare)
- Facial and nasal surgery