Dr. Alien(1989)

When the mysterious and sexy Ms. Xenobia takes over the biology class at the local college, the dating life of supergeek Wesley Littlejohn takes a serious turn. Littlejohn agrees to be a lab rat for the professor's unusual vitamin research study. Now, thanks to some out-of-this-world supplements, he's been transformed into the campus stud. But Xenobia has ulterior extraterrestrial motives in this sci-fi sex comedy.