Definately take your meds, but wear a high, oil free Spf, and a hat(baseball cap/visor if you want, whenever possible). Reapply the spf frequently, esp. after swimming/sweating. You should apply the spf 30 mins. before any exposure, but that may not be possible in your case--just make sure you apply it!
Have a great time!
May you have enough happiness to make you sweet, enough trials to keep you strong, enough sorrow to keep you human, and enough hope to keep you happy.