[Purpose]
The purpose of this study was to demonstrate the effectiveness of Kampo medicines, from the aspect of cost effectiveness. We obtained judgment criteria by analyzing past published papers and implemented our study according to criteria about the kinds of formulations and diseases that were suitable for pharmacoeconomic analysis.
[Method]
First, we extracted the original, clinical, and NHI price listed formulations (EA) from each published paper, by searching for Japanese key words such as “_??__??_ (Kampo)” or “_??__??_ (economic)” in the databases of “Igaku Chuo Zasshi” and “Institute for Health Economics and Policy.” Considering the importance establishing a controlled treatment method in pharmacoeconomic analysis, we defined papers with a comparative control (Comp) as one judgment criterion (1), then extracted these data; and analyzed how target (diseases and formulations), controlled formulation, measurement outcomes, and “Sho” (patterns or syndromes) were handled in each paper. Secondly, we defined those formulations which had been referred to many times in the EA as our second judgment criterion (2), because we thought they had abundant and clear outcomes, and then implemented an outcome analysis of them.
[Results and Discussion]
Judgment criterion (1): The number of formulations, and the total number of papers referring to a Comp (38 articles) were 25 and 41 (Shoseiryuto [4], Shosaikoto [4], Kyukichoketsuin [3] in descending order) respectively. Approximately two-thirds of target illnesses covered in these papers were gastrointestinal diseases, infectious diseases, ear nose and throat diseases; and in women, pregnancy or delivery-related diseases. Concerning outcomes, only 10.5% of the papers measured human outcomes such as quality of life (QOL), which might suggest that the implementation of cost effectiveness analysis was difficult. The results of analyzing how to handle “Sho” suggested that Kyo-sho or Vacuity-sho patient formulations tended to exert their treatment effects relatively, even without consideration for “Sho”.
Judgment criterion (2): Using EA prices, we expedientially defined frequently referred formulations as those referred to in 15 or more of the total research paper number, and then extracted them. As the result of this extraction, 6 formulations (Hochuekkito, Keishibukuryogan, Shishihakuhito, and etc.) were obtained. Among these formulations, Shishihakuhito had high rates (88.2%) for achieving treatment goals, including the improvement of skin symptoms such as erythema and pruritus.
[In Conclusion]
A comparison between Kampo and Western medicines was not simply applicable, due to large differences between their mechanisms of action, and the ways they exert their effect, even if their ultimate effects are the same. We would need to create a study plan which would cover human outcomes when making a further pharmacoeconomic study, because Kampo medicines do have a good chance of improving QOL. We would even say that Vacuity-sho formulations given to patients could easily work, without consideration for “Sho”.