it's worth doing a study. the drug can have serious side effects. kyle hasn't had any and has enjoyed his new head of hair. >> always wanted an '80s hockey mullet so maybe going towards that. >> why would a drug for arthritis help grow hair? researchers think rheumatoid arthritis and the kind of condition kyle has are both related to the immune system. kyle's doctors hope at some point he can stop because it has side effects and it's really expensive. chris and kate? >> really amazing the hair growth he had back and at least it gives him something, good for him, and had a that could mean for a lot more men we'll see. >> i'm happy for him, but elizabeth said that it's not for regular mail pattern baldness. >> you can learn from these things though. >> i'm happy, i'm torn. very happy for this kid, especially what he grew up with and there's a lot of people who have immune disorders like that, but you had me there for a