Brief Answer:
Nose bleeds:

Detailed Answer:
Hello and welcome,

There are many different reasons that noses can bleed, some more common and some more rare.

Nose bleeding means that small blood vessels in the lining of the nose have become irritated or broken.

The most common cause of nose bleeding in children is nose picking.
Dry air is also a more common cause for nose bleeds.

Things that inflame the mucus membranes of the nose such as nasal allergies, colds, and sinus infections can do it.

Other causes include things that thin the blood such as aspirin and blood thinner medications, and rare disorders that causes bleeding.

Some chemicals can be irritating, such as bleach, ammonia, and cocaine.

Foreign objects up the nose, and nasal sprays can cause physical trauma that can cause bleeding

Much less common are nasal polyps and tumors in the sinuses or nose.

I hope this clarifies for you the causes of nose bleeding. Please let me know if I can provide further information.

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