Having very dry lips from past 2-3 weeks,drinking enough water.have orthodontic braces and undergoing some course of antibiotic from past 4 days.help?

Not from braces: Dry lips can be from mouth breathing (especially if nose clogged), licking lips and causing them to chap, medications, change in diet, allergies, etc. Try using a lip balm such as Chap-Stick, or put Vaseline Petroleum Jelly on your lips. If it doesn't clear in a few days see your General Dentist, Orthodontic Specialist, or Primary Care Physician for further examination.