Dermaline was an injectable drug used to prevent sunburns.
In 2376, Neelix was so excited to be on a beautiful Norcadian beach that he forgot to take his dermaline injection and ended up getting severe burns. (VOY: "Tsunkatse")
Dermaline gel was used to treat patients who had suffered first and second degree burns. (ENT: "Dear Doctor", VOY: "Deadlock")