What can I do to get rid of a dry cough? I've had it about 3-4 weeks now and was on antibiotics for it which has not helped

Cough. Go back and see your doctor. It's common to get a post viral hypersensitivity in the lungs meaning after a viral or bacterial Infection your bronchioles are hypersensitive and respond to any stimulus causing cough. There is medication that can help . .