Care to be more specific? Why do you want to do this internship? What are your skills? What region of the world interests you? Why "abroad"? Do you have any experience in a clinical setting? How would you like to spend your days? Would you expect pay or a stipend?
I don't mean to be negative, I'm actually someone looking to help. If you're interested in Latin America PM me and we'll talk.
-C.J.