ycline antibiotic which is useful intravenously (IV) to treat serious bacterial infections such as respiratory, skin, urinary tract and lyme disease infections and prevents anthrax however it is not for viral illnesses such as colds or flu and carries risks such as tooth staining in kids and sun sensitivity. It is administered as an IV drip by healthcare professionals and it works by killing bacteria and requires protection from light during infusion and with specific handling for reconstituted solutions to maintain stability.