The cure depends on the cause. The most likely cause is chronic bacterial infection of the nose, sinuses or gums, sometimes infection with a fungus. Whatever the cause, the “blockage” must be opened for, whatever the cause, it will continue to grow in a situation of poor drainage. In addition to whatever antibiotic might be appropriate, nasal irrigations 2-3X/day with “nasal saline” would almost definitely, help.
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Please, what is d solution to bad odor nose smell