If you're dealing with a fever, facial pain, severe congestion or prolonged symptoms, green mucus may also suggest a sinus ...

Your mucus can turn green from the even larger build-up of dead ... When blood from your nasal lining dries, it can mix with the mucus and turn brown. But brown mucus isn’t always because ...

Brown mucus could suggest possible infection, but also air pollution or excess smoking. Carleton-Nathan says yellow, green, red, pink or brown mucus is not an immediate cause for alarm.

Julia Calderone wrote an earlier version of this post.