Can nosebleeds cause anaemia?

Possible. Nasal bleeding is one of the common clinical symptoms and can be caused by nasal and sinus diseases, or by systemic factors. Lighter cases only have blood in the snot or aspiration back to the snot, while heavier cases can bleed up to hundreds of millilitres, and a large amount of bleeding at one time can lead to shock, and a small amount of bleeding many times can lead to anaemia.