I always have my little tube (similar to the Tide Stain Remover tube) of After Bite on me. It is the BEST stuff for bug bites and stings! It calms the itching right down and it prevents the bite from swelling, which is great for me 'cause ant bites continue to swell on me 'til I put something on them, which used to not be for hours 'til I found After Bite! Not to mention the itching from bug bites, which After Bite takes care of.
(Note: I like the original liquid-in-a-plastic-tube kind better than the gel-in-a-squeeze-tube kind, as it works better for me.)
http://www.tendercorp.com/afterbite.html 