Causes of Excess Mucous

isick child image by Renata Osinska from

Mucous is one of the body's natural defenses against illness and infection. Mucus, which may flow from the nose and down the back of the throat, serves many purposes, such as lubricating and blocking irritants from the sinuses and airways. The excessive production of mucous occurs for numerous reasons. Some of the most common include allergies, sinusitis and any other respiratory illness. There are medications that can reduce the production of mucous and help thin the secretions.


Drinking milk, inhaling pollens or exposure to pet dander are all potential allergens that can trigger the production of excess mucous. Any type of allergy, whether it is a food or airborne agent, can trigger the immune system to respond in certain ways. The Mayo Clinic explains that part of this immune response is to produce mucous, as a way to eject the allergen from the body. Sneezing, coughing and a running nose are just some of the signs of excess mucous produced due to allergies. The throat may be sore from the mucous drainage and coughing. Post-nasal drip, the drainage of mucous down the back of the throat, can lead to bad breath and the frequent urge to clear the throat. Treatment of allergies often consists of antihistamine medication and prevention of exposure to the allergens. Antihistamines block the body's chemical response to the allergen. The body produces histamine to trigger the immune response to fight off the allergen.


Sinusitis, an inflammation of the sinuses, is actually a symptom of another issue. Common causes of sinusitis include infections from viruses, bacterium or fungi. The National Institutes of Health explains that the sinuses can become inflamed when too much mucous builds up from the irritants causing the infection. The small hairs in the sinuses help move mucous out of the body. When these hairs stop working due to the underlying condition, the result is the body sensing a foreign blockage and producing more mucous. Other symptoms of sinusitis include bad breath, coughing or nasal congestion. Treating the underlying cause, whether it be allergies, a cold or an illness, will reduce the production of mucous. Infections are often treated with antibiotics or antifungal medications, unless they are due to a virus. A virus must be allowed to run its course, but treatment of the symptoms can be effective in minimizing discomfort. This can include pain medication, cough suppressants and other such medications.

Cystic Fibrosis

One chronic, more serious, cause of excess mucous is an inherited disease called cystic fibrosis. The National Institutes of Health describes this disease as one that causes thick, sticky mucus to build up in the lungs and digestive tract. It often results in early death. The excessive collection of mucus can cause life-threatening lung infections and serious digestion problems. The treatment of cystic fibrosis is comprehensive and usually includes treating the infection or other complications that surround the illness. There is no known cure, but patients can manage the symptoms to improve quality of life.