The causes of nosebleeds from colds generally consist of chemical factors, physical factors, medication factors and so on. 1. Chemical factors: the cold itself can lead to nasal mucosa congestion, edema and so on. If the nasal mucosa is damaged, leading to the rupture of capillaries, this will lead to nose bleeding. 2. Physical factors: patients with colds will have a runny nose, sneezing and so on. The vibration of running nose and sneezing may cause the nasal mucous membrane to break, which in turn leads to nosebleed. 3. Drug factors: patients with colds, if at the same time taking antiplatelet aggregation drugs, such as aspirin, colds at the same time may aggravate the role of anticoagulant drugs, leading to nosebleeds. There may be other reasons for nosebleeds, such as hematologic disorders, etc. It is recommended to consult a doctor in a timely manner to identify the specific cause and follow the doctor’s instructions for treatment.