"A woman came in for a baby check with her 6-month-old and she had what looked like chocolate milk in the baby’s bottle. So he started explaining to her as kindly as he could that she shouldn’t be giving her baby chocolate milk. At which point she interrupts him and says, ‘Oh that isn’t chocolate milk. It’s coffee! He just loves it!"
Read full article: http://www.buzzfeed.com/lukelewis/16-doctors-on-the-dumbest-patients-they-have-ever-treated#.jt5OkdYr
Related article: Medical testing: is it about quality?