Frequent phlegm and sometimes a brief stoppage of breathing during sleep should alert you to obstructive sleep apnea syndrome (OSAS), which is caused by an upper airway disorder.
Obstructive sleep apnea syndrome is a sleep breathing disorder. Upper airway diseases not only cause sleep apnea due to the narrowing of the pharyngeal cavity, causing sleep apnea, but also cause an abnormal increase in the secretion of respiratory glands, resulting in frequent phlegm.
Frequent phlegm, along with sleep apnea, can be detrimental to an individual’s health, so it is advisable to seek medical attention for early intervention if you experience this abnormal symptom.