what is the best medicine to take for hives?

Every year, when I go on vacation to the same location in BC, I get hives.  I used to think it was from excessive heat, as the location can be extremely hot.  But, this year we've gone later in the year, and have not been exposed to hot weather.  I used to think it was from eating excessive amounts of fruit, except this year I have not indulged in large amounts of fresh fruit, like cherries, grapes, watermelon, etc.  I've only had a small amount of fruit.  I used to think it was from the shrimp, as while on holidays, I ate shrimp all the time.  But this year, I have not touched it.

The only thing I can think of, that would have contributed to my itchy rash, (Hives?), would be my wipe on tanning lotion?  Is it possible, that there is an ingredient in there that I would be reacting to?  My rash is limited to my legs only, which is the only location where I've used it.

And, what should I be taking to reduce the itching?  It's awful!