Nosebleeds occur when the tiny blood vessels inside the lining of the nose break and bleed. The most common causes include:

• Dry air, which can dry out and irritate the nasal membranes, making them more likely to bleed.
• Nose picking or scratching inside the nose.
• Blowing the nose too forcefully.
• Injuries such as trauma or burns to the nose.
• Allergies, colds, sinus infections, and other irritations.
• Use of certain medications like blood thinners (aspirin, warfarin).
• Chemical irritants like ammonia or snorted drugs (cocaine).
• Frequent use of nasal sprays or decongestants.
• Structural issues such as a deviated septum.
• Foreign objects in the nose.
• Less common causes include bleeding disorders (like hemophilia), nasal tumors, or hereditary conditions affecting blood vessels.

Nosebleeds typically come from the front part of the nasal septum and are most often not serious. They may increase during winter when air tends to be drier and people have more colds. In general, nosebleeds result from irritation, injury, or dryness of the nasal lining, and most cases can be managed with simple care.