Mucus in the throat can be annoying, but it is almost always present in small amounts. In some cases, however, mucus can become excessive and lead to significant discomfort. There are many reasons why this can occur: seasonal allergies, sinus troubles, or even minor irritants. Most of the time, the underlying problem is simple and can easily be fixed, but in other cases, it can be an indicator of more severe medical issues.
One of the most common causes for mucus in the throat is post-nasal drip. The glands in the lining of the throat and nose produce between 4 to 8 cups (nearly 1 to 2 liters) of mucus every day. Over time, this mucus can accumulate, getting thicker and becoming more noticeable. This can happen due to a cold, sinus infection, or the flu, but those who live in excessively cold or dry areas, as well as people with deviated septums, may also suffer from post-nasal drip.
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Seasonal allergies and irritants may also be to blame. Many people suffer from seasonal allergies, and along with coughing, sneezing, and watery eyes, most people may notice a marked increase of phlegm production in the throat. This over-production is not only annoying but may also cause a sore throat, nausea, and stomach aches. Irritants such as smoke, airborne chemicals, and pollution can settle on the lining of the throat or cause inflammation, which may also create an excess of mucus production.
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Other mild causes of mucus in the throat can include acute or chronic sinusitis, as well as certain viral or bacterial infections. Some foods and liquids may also cause an extra phlegm in the throat, such as caffeinated beverages, spicy meals, and dairy products. Food-related allergies can be to blame as well. Pregnancy may also create an over-production of mucus, as high levels of estrogen may not only create more phlegm, but may also cause it to become very thin or very thick.
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There are also a few more serious reasons for this problem. Conditions such as laryngopharyngeal reflux disease (LPR) can cause the body to produce more mucus than usual. Ailments such as catarrh and pharyngitis, as well as tonsillitis and strep throat, can cause excess mucus as well, as can certain viral conditions like whooping cough, mononucleosis, and chicken pox.