Characteristics of “hard-to-use” press-through-package sheets: An analysis of information collected by marketing specialists of a Japanese medical wholesaler

Background: Press-through-package (PTP) sheets are common forms of packaging for medicines in Japan. However, patients and/or pharmacists have reported difficulty in extract-ing tablets or capsules from some PTP sheets. Objective: We used postmarketing surveillance data to identify the characteristics of PTP sheets that patients and pharmacists feel are “hard to use”. Methods: Marketing specialists of Toho Pharmaceutical Co., Ltd. canvassed patients and medical workers during November 2014–April 2016. Among 1,129 anonymous reports of products being “hard to use”, we identified 39 products with 5 or more reports (Problem group). We compared the sizes of the drugs and PTP pockets, the size ratio, the material used for the front of PTPs, the shape of the pockets, the thickness of the pocket wall, and the force needed to release the drug from the PTP (press-out force: POF) in this Problem group with those in a Control group of 97 problem-free products. Results: Logistic regression analyses revealed that a bigger pocket, a smaller drug size and a smaller drug-pocket size ratio increase the risk of being “hard to use”. Regarding the material, aluminum, PCTFE and PE increase the risk, while PP and PVC decrease the risk. Other factors had no significant influence. Conclusion: Pockets in PTP sheets should be designed so as to minimize the gap between the drug and the pocket, and PP or PVC should be used as the front material instead of aluminum, PCTFE or PE. Our results suggest that marketing specialists can play effective roles in postmarketing surveillance.