Clear mucus is, generally, normal mucus. Cells that line the sinus passages produce mucus to protect the lining of the mucus membrane. The main purpose of mucus in its normal state is to filter air when a person breathes. A certain amount of clear mucus is healthy and necessary. The production of excess clear mucus, or different types of mucus, can indicate a problem.
It is normal, healthy, and necessary for a certain amount of clear mucus to be present in the sinus passages. This kind of mucus acts as a defense against airborne particles. It protects the lining of the nose's mucus membrane and helps keep dust, pollen, germs, and other debris from getting any farther into the body. In this normal production state, the presence of healthy, clear mucus rarely is noticeable or bothersome. Generally, a person only needs to become concerned when there is too much clear mucus or the mucus isn't clear, indicating an infection.
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Some of the most common causes of excess clear mucus include allergies, hay fever, and the common cold. Many of these conditions can be treated with simple home remedies and over-the-counter medications. Other causes of excess clear mucus, such as acute sinusitis and the flu, might require a doctor’s attention. Excess clear mucus usually drains by way of post-nasal drip, which is often marked by a running nose, nasal congestion, and tickling or soreness in the throat.
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If other types of mucus are present, it might mean the person is suffering from a more serious condition. For example, green, yellow, or brown mucus could indicate a viral or bacterial infection. Viral infections, such as the flu and the common cold, are usually cared for by treating the symptoms rather than the condition itself. Bacterial infections, on the other hand, generally require antibiotics. These antibiotics will treat the secondary nasal bacterial infection, but a doctor also will need to diagnose and treat the primary illness causing the infected mucus.
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Common home remedies and over-the-counter medications can help treat simple post-nasal drip and even alleviate the symptoms of viral infections causing infected mucus. Such remedies include taking a steam-filled shower or using antihistamines or nasal decongestants in pill or spray form. If infected mucus is present, it is best to see a doctor. Infected mucus often means a bacterial infection is present, and a bacterial infection generally requires a doctor’s attention and prescription treatments. It is always best to see a doctor when the nature and cause of the infected mucus are unknown.