A sore throat is a condition that involves pain and swelling in the throat. The most common types of sore throat are caused by external pathogenic invasion and can usually be treated easily. However, if left untreated, ignored, or recurrent, sore throats can become chronic.
Wind and changes in temperature are the main causes of acute sore throat. Wind-heat is the most common pathogen, invading the body through the mouth and settling in the throat, causing inflammation and pain. If the heat is strong enough, it can generate toxicity-heat, leading to swelling and severe pain. A strong wind-heat pathogen can potentially spread to the lungs and stomach. This invasion can be facilitated by improper treatment and is more likely to occur in individuals with preexisting internal heat from their diet or chronic liver qi constraint.
In hot or humid climates, damp-heat may be the dominant pathogen. Unlike wind-heat, damp-heat develops gradually because the presence of dampness prevents the full expression of heat. The dampness prolongs and complicates the heat elements, making it difficult to resolve the condition. Damp-heat is associated with prolonged illness and is more likely to become a lingering condition if ignored or mismanaged. It can also reappear when the person is weakened or under stress.
Internal heat can be generated by consuming excessive amounts of spicy or rich foods or alcohol. If left unchecked, it can smolder at a low level, irritating the tissues of the upper respiratory and digestive tracts and contributing to low-grade inflammation of the throat. Chronic heat retained in the throat can suddenly flare up into a severe and suppurative sore throat when triggered by an invasion of wind. Heat in the stomach can also lead to problems with reflux and throat irritation, which may go unnoticed by the person and only occur during sleep.
The overuse of antibiotics or bitter, cold, heat-clearing herbs in the treatment of repeated sore throats or other upper respiratory tract infections can damage the spleen and kidney yang qi. The cooling nature of these drugs does not clear the heat, but instead leaves a residue of accumulating dampness, setting the stage for recurrent infections.
Emotions such as anger, rage, resentment, frustration, and bitterness can constrain liver qi, which can in turn affect the throat. The throat is an energetic "choke point" where a number of channels converge, making it easy for qi to get stuck, as seen in conditions such as plum pit qi. Common complications of constrained liver qi can contribute to or predispose an individual to the development of sore throat. Constrained qi can invade and weaken the spleen, hinder the movement of fluids, and congeal dampness into phlegm. Qi and phlegm constraint can be further complicated by heat, fluid damage, yin deficiency, or blood stasis.
Excessive use of the voice by singers, politicians, and professional talkers can deplete the qi and yin of the throat. Smoking cigarettes or other substances introduces heat directly into the lungs, drying out the delicate respiratory surfaces and damaging lung yin. Persistent exposure to volatile chemicals can have a similar effect.
Any factor that harms the kidneys, especially kidney yin, can lead to chronic sore throat. The most common causes are those that first damage the lungs, which then rely on the kidneys for support. Living in a very dry environment, smoking, and recurrent episodes of acute sore throat from wind-heat or lung and stomach heat can eventually damage lung and kidney yin. Kidney yin can also be depleted by overwork, aging, excessive sexual activity or drug use, or following severe febrile diseases.