Celebrities who were practising doctors before they became famous

Michael Crichton, a Harvard Medical School graduate, wrote 'The Andromeda Strain' during medical school and sold its movie rights before graduating in 1969.

Ken Jeong practiced internal medicine while performing stand-up comedy, then left medicine after his role in 'Knocked Up'.

Khaled Hosseini earned his medical degree from the University of California, San Diego, School of Medicine in 1993.

Che Guevara and Sir Arthur Conan Doyle left medicine for other careers, according to the article.

Michael Crichton wrote 26 novels, with over 200 million copies sold, including 'Jurassic Park' and created 'Westworld' and 'ER'.