Although cold sores are most common around the mouth, they can appear in other places, including inside the nose. Cold sores result from an infection with the herpes simplex virus (HSV).
The condition is triggered by Staphylococcus aureus bacteria (which thrive in moist environments, like inside the nostrils) or physical irritation (from nose blowing, say, or booger picking). In less ...
Symptoms include painful swelling in the nostril and redness ... Your healthcare provider can diagnose a pimple inside the nose by performing a physical exam of your nose and asking you questions ...