Occasionally I'll develop a dry foreskin from too much bathing/showering (it's the sub tropics down here and not uncommon to walk in the house, take a cool shower on the terrace and jump in the pool for an hour five or six times a day). Two things keep me from developing any serious dermatological problems: if I'm starting to feel a bit too dry I squirt a couple of drops of baby oil (mineral oil) inside my foreskin and thoroughly rub it around the head of my cock as well as leave a bit glistening on the outside. When I'm otherwise doing fine, I still keep house by pulling everything back, drying my tool off, and liberally dust everything inside and out with plain corn starch. Both stop normal wear and tear skin irritation in its tracks.
Special note: after camping in the Sonoran Desert and fucking like minks every 20 minutes for several days, the head of my dick was worn almost raw. It was amazing how quickly it healed and everything returned to normal after several applications of generic triple-antibiotic cream. Neosporin would probably work as well. But then I knew I didn't have an STD, just an overworked penis.