The appropriate use of OTC drugs in multiple medication.

• Project/Area Number: 24590634
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Medical sociology
• Research Institution: Showa University
• Principal Investigator: IWASE MARIKO 昭和大学, 医学部, 助教 (70424273)
• Co-Investigator(Kenkyū-buntansha): NISHIMURA Yuki 昭和大学, 医学部, 講師 (40276572) ; KURATA Norimitsu 昭和大学, 教養部, 教授 (80231299)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Project Status: Completed (Fiscal Year 2014)
• Budget Amount: ¥4,160,000 (Direct Cost: ¥3,200,000、Indirect Cost: ¥960,000); Fiscal Year 2014: ¥650,000 (Direct Cost: ¥500,000、Indirect Cost: ¥150,000); Fiscal Year 2013: ¥1,300,000 (Direct Cost: ¥1,000,000、Indirect Cost: ¥300,000); Fiscal Year 2012: ¥2,210,000 (Direct Cost: ¥1,700,000、Indirect Cost: ¥510,000)
• Keywords: 一般用医薬品 / チトクロームP450 / セルフメディケーション / 薬物相互作用

Outline of Final Research Achievements

OTC (Over the counter) drugs have been used for a long time period, however, there is a little information concerning to the drug-drug interaction. In the current study, we investigated the inhibitory effects of commonly used OTC drugs on cytochrome P450 (CYP) activities using human liver microsomes. The possibility of the OTC drugs to cause drug interactions with the prescribed drugs in clinical situation were predicted by using the equation recommended by The Ministry of Health, Labour and Welfare. The results showed that among the studied 26 OTC drugs, bromohexine hydrochloride, tipepidine hibenzate and difenidole hydrochloride extensively inhibited CYP2D6 activity, suggested the possibility of drug interaction at the commonly used clinical dosage level. Because these OTC drugs are considered to use concomitantly with various therapeutic agents, the appropriate medication interview to the patients to avoid the risks of adverse reaction.

Research Products

• [Presentation] The inhibitory effects of gastrointestinal and respiratory drugs on human hepatic microsomal cytochrome P450 activities (2014)
  • Author(s): Mariko Iwase, Yuki Nishimura, Norimitsu Kurata, Atsushi Tsukurimichi, Katsuji Oguchi
  • Organizer: 19th North American ISSX and 29th JSSX meeting
  • Place of Presentation: San Francisco, California, USA
  • Year and Date: 2014-10-19 – 2014-10-23
• [Presentation] 消化器官用薬のcytochrome P450酵素活性に対する阻害効果 (2013)
  • Author(s): 岩瀬万里子、西村有希、倉田知光、小林真一
  • Organizer: 第34回日本臨床薬理学会学術総会
  • Place of Presentation: 東京
• [Presentation] Drug-drug interaction with OTC drugs-The inhibitory effect of NSAIDs and cough suppressants on CYP activities (2012)
  • Author(s): Mariko Iwase, Yuki Nishimura, Norimitsu Kurata, Naoki Uchida, Shinichi Kobayashi
  • Organizer: 6th European Congress of Pharmacology
  • Place of Presentation: Granada, SPAIN
• [Presentation] 一般用医薬品のcytochrome P450酵素活性に対する阻害効果－総合感冒薬配合成分による影響－ (2012)
  • Author(s): 岩瀬万里子、西村有希、倉田知光、内田直樹、張本敏江、三邉武彦、戸嶋洋和、川上桃子、小林真一
  • Organizer: 第127回日本薬理学会関東部会
  • Place of Presentation: 東京