- Post-nasal drip, also known as PND, is a chronic condition where the sinuses produce excessive mucous. As a result, the sufferer experiences a number of symptoms associated with a constant flow of mucous flowing down the back of the throat such as sore throat, coughing, hacking, snorting, bad breath, feelings of nasal congestion, and even nausea and vomiting from the pooling of mucous in the stomach.
A number of possible causes exist for post-nasal drip. The most common is rhinitis, an allergic response in which the tissue of the sinuses becomes inflamed. Chronic acid reflux has been known to create the same effect. Less commonly the cause is a swallowing disorder which creates a build-up of mucous. - Black discharge in the mucous of PND has two possible causes. The first is that the sufferer has been a marijuana user. While PND discharge will sometimes be brown for tobacco users, the long-term effects of marijuana use creates black mucous. The other possible cause is sinusitis. This can be an acute or chronic secondary bacterial infection, which can lie dormant for up to a year after the sufferer has experienced a viral-based upper respiratory tract infection like the flu or pneumonia.
Sinusitis can affect any of the four main sinus chambers behind the nose and need not necessarily include pain or sinus pressure. In these cases, it is always associated with chronic halitosis, as the infection is necrotizing the sinuses' outermost layer of cells, creating black discharge. - A number of drugs are used to treat sinusitis and stop the black discharge. Corticosteroids such as prednisone are prescribed to reduce inflammation of the sinus cavities while mucolytics like Mucinex thin the consistency of the mucous so that it can be cleared more easily. In the meantime, large doses of trimethoprim-sulfamethoxazole or other antibiotics are prescribed for 3-5 days in order to kill the source of the infection.