acne
"I used the samples my doctor gave me for oily skin.  It smelled terrible, but it really worked for my oily skin!  I got the prescription and, guess what...  it smells great and DOESN'T WORK!  I brought it to my doctor and she compared the  labels and they matched up.  I thought maybe it was a fluke, so I got the medicine again and same thing...  good smell, but doesn't work at all.  It was so depressing because I had finally found something that controlled my oil, but I can't ask for a lifetime of samples!  At $50 a pop (with insurance), I'm not going to keep trying it."