When you have allergies, the best thing you can do for yourself is to avoid your triggers. But first, you have to find out what your triggers are. Sure, if you start sneezing and rubbing your itchy eyes every time you come into contact with your sister's cat, you probably already know cats are a trigger.

But what if you go outside in the late summer and start having those allergy symptoms? Is it the ragweed that's in bloom everywhere that's causing them? Or maybe the leaves that are starting...