I am very new to running...well, fitness in general. Over the last year and a half I've made major changes in eating and fitness and I'm finally to the point where I can run comfortably for a while. I am going to do my first official 5k Saturday. It has only happened a few select times but each time I notice that I have pushed myself harder - past what I thought my boundaries were. Whether it's running faster or for a longer period of time. Anyway, what happens is after I've cooled down I have a major sneezing attack and then what seems like a full blown allergic reaction. Last night the sneezing went on for a full ten minutes...stop then start...ugh. Benadryl helped eventually but today it feels like I'm getting over a cold. I am running in my first official 5k Saturday and I'm wondering if I should take a Benadryl before running. They usually make me sleepy so I'm a little hesitant..but at the same time I know I'm going to try and push myself and I really don't want to deal with this mess of sneezing and runny nose etc for another round. Help!?