Do you know what is the concept of P-drugs ?

P-drugs means Personal/Preferred drugs. All of us from medical school know about the concept of 'drug of choice', which means the best drug for a given medical condition. Then why and what is P-drug concept required. Go to this link for a detailed overview http://www.ijp-online.com/article.asp?issn=0253-7613;year=2007;volume=39;issue=3;spage=165;epage=167;aulast=Parmar