Is there a specific drug or antibiotic i use to treat exercise-induced gastrointestinal distress?

From your question, it seems like you are referring to what is referred to as "runner's diarrhea", a form of colitis associated with long-distance running. First, there's no real scientific consensus on the cause of this and therefore no agreed upon treatment within the medical community. Antibiotics are unlikely to help, however, diet modification may be the first thing to look at.

No, no specific medications, although sometimes anti-spasmodic medication‘s can make irritable bowel syndrome better. Initially, I would treat this by increasing the amount of fiber in your diet. Be sure to add extra hydration. If you do not get relief with this, then I would see the primary care doctor or your gastroenterologist. Good luck.