"Why does blood from a nosebleed sometimes come out of the mouth?"

Nosebleeds can sometimes flow out of the mouth, which may be caused by various reasons such as normal phenomena, excessive bleeding, nasal foreign bodies, incorrect body positions, and Eustachian tube dysfunction. It is recommended to seek medical attention promptly and follow the treatment measures provided by a healthcare professional. The following is a detailed analysis:

1. Normal Phenomenon

The nasal cavity is connected to the pharynx through the nasopharyngeal isthmus, which serves as a passage between the two. When blood vessels in the nasal cavity rupture, the blood may flow into this passage and further into the pharynx. As the pharynx is connected to the oral cavity, the blood can flow through the opening of the pharynx into the mouth, resulting in blood coming out of the mouth. Gently tilt the patient's head backward and gently pat their forehead and bridge of the nose with a cold, damp cloth or ice pack for about 5 to 10 minutes without applying excessive force.

2. Excessive Bleeding

When there is a significant amount of nosebleed, the blood may not be able to drain solely through the nasal cavity, especially if the nasal passage is obstructed or the bleeding site is deep within the nasal cavity. In such cases, the blood may flow into the pharynx along the posterior nasal passages and subsequently enter the oral cavity through the throat, causing blood to come out of the mouth. Apply a wrapped ice pack to the patient's forehead as directed by a healthcare professional, for 5-10 minutes at a time, taking care not to apply ice for too long to prevent frostbite.

3. Nasal Foreign Bodies

Foreign bodies in the nasal cavity can irritate or damage the nasal mucosa and blood vessels. This irritation or damage may lead to the rupture of blood vessels under the nasal mucosa, causing nosebleeds. As the nasal cavity is connected to the pharynx, the blood may flow into the oral cavity along the pharynx, eventually coming out of the mouth. Small foreign bodies can be gently removed with tweezers under medical guidance, while larger ones may require surgical removal under a nasal endoscope.

4. Incorrect Body Position

Tilting the head backward during a nosebleed may cause the blood in the nasal cavity to flow into the pharynx due to gravity, rather than draining through the nasal cavity. Once the blood enters the pharynx, it may exacerbate the nosebleed and lead to blood flowing out of the mouth. Maintain an upright or slightly forward-leaning head position under medical guidance, breathe through the mouth to prevent blood from entering the esophagus or trachea, and gently stuff the nasal cavity with cotton balls or gauze.

5. Eustachian Tube Dysfunction

The Eustachian tube connects the nasal cavity and the throat, helping to balance the pressure between them. When the Eustachian tube malfunctions, blood from the nasal cavity may flow backward into the throat, causing nosebleed to enter the oral cavity. Follow medical instructions to use medications such as oxymetazoline nasal drops, xylometazoline nasal drops, or mometasone furoate nasal spray. It is also recommended to maintain humid indoor air, keep the nasal cavity clean, avoid strenuous exercise, maintain a balanced diet, and engage in appropriate exercise to aid in recovery.