"Have you ever matriculated in or attended any medical school or health profession as a candidate for a professional degree?"
"Have you previously, or are you currently applying to a health profession school other than dental school?"
The ADEA application will ask you these two questions. The first one you answer no and the second one you answer yes.
A box will pop up asking "Indicate the school(s), type of program, year applied, and if you were accepted". Just put down the pharmacy school and that you were accepted and that's it.
An interviewer may choose to ask you why you didn't go and that gives you a chance to say why you chose dentistry over pharmacy. In my opinion in this situation you already look brave because you were accepted to a program and chose to decline and pursue something that wasn't guaranteed.
I don't think this question on your application though will stop you from being interviewed.