What are the reasons for yawning and tearing up?

The main reasons for tearing up while yawning are as follows: 1. Normal phenomenon: During yawning, the facial muscles tense and contract, which may compress the nasolacrimal duct, preventing tears from draining into the nasal cavity in a timely manner, thereby causing tears to overflow. 2. Eye strain: Prolonged use of the eyes, such as watching mobile phones or computers, can lead to eye fatigue, resulting in increased tear secretion when yawning. 3. Lack of sleep: Insufficient sleep can cause brain fatigue, leading to frequent yawning and impaired tear drainage, resulting in tearing. 4. Medical conditions: Factors such as nasolacrimal duct obstruction or abnormal nerve regulation may also cause tearing during yawning. Tearing while yawning could be a normal phenomenon or may be caused by eye strain, lack of sleep, or underlying medical conditions. If discomfort occurs, it is recommended to seek medical attention promptly.