I have been on 19 cruises with an upcoming one to the Med in September.
I have been fortunate to sail on many lines, Celebrity, RCCL, Carnival, Princess, NCL, & Holland America.
During the last 2 NCL cruises I have experienced HIVES beginning on the night of the 3rd day.
The hives only appear on my chest, and legs below the knee.
I have NEVER had any problems at all on any of the other cruise lines no matter the length of the cruise.
I eat the same things on all the cruises, and cannot figure out why this only happens on NCL. My first inclination is to think it may have something to do with the laundry detergent which the sheets, and towels are washed in. However I wear pajamas and long socks so the sheets don't touch my legs.
Absolutely nothing to do with NCL unless you may have an alergy to the soap products they use. You may want to bring your own. My husband who has lots of skin alergies has never had trouble with any cruise ship. I just got back from the Sun, no problems, nor have I had any on my other 7 NCL cruises.