I want to know how I can tell if my friend is taking ecstasy ?

He has been acting really weird and leaving home early. Also he has been really tired and loud and touching everything. He has been telling our friends and I that he loves us. The next day, he doesn't remember anything that happens, and he has been sick with runny noses and he has been extremley hot, and when he is asked if he is taking drugs he acts like he doesn't know what I'm talking about. He claims that he is sick. Please help I want to help him before something bad happens.