Will bronchitis infectio go away by itself?

Yes: It will. In fact, there's no real treatment for acute bronchitis in patients with normal lungs. Antibiotics are often used, but they're essentially placebos.

Bronchitis Tx.: 95% of the time, acute bronchitis is a viral infection, so the mainstay of treatment would be steroids, usually taken in pill form. For the minority of cases that could be bacterial, we tend to add in an antibiotic, like Zithromax or Levaquin, (levofloxacin) to be complete. However, the steroid is the real mandatory part of the treatment,