By SaKm | Apep Bar Investigations | November 13, 2026
Japan’s prescription herbal-medicine industry poses an uncomfortable question: when centuries-old healing formulas enter modern national insurance and pharmaceutical manufacturing, who captures the value?
A traditional system, a concentrated commercial market
Drugmaker Tsumura reports that it supplied 129 of Japan’s 148 approved prescription Kampo formulations and held 84.6% of the prescription Kampo formulation market at the end of fiscal 2024. These are company-reported figures and should be assessed against independent market data. Source: Tsumura domestic business investor information.
Its 2025 integrated report describes an extensive value chain spanning medicinal-plant sourcing, manufacturing, physician education, distribution, and expansion into China. Source: Tsumura integrated reports. That infrastructure can improve consistency and access, but high market concentration also warrants scrutiny of pricing, supplier bargaining power, procurement, and the influence of manufacturer-supported research.
What reimbursement proves — and what it does not
Japan’s national health insurance covers 148 prescription Kampo formulations according to a 2024 physician survey. Reimbursement confirms their formal place in the system, not uniform clinical effectiveness. Source: 2024 survey. For example, a 2019 analysis of daikenchuto studies found benefits in pooled results that lost statistical significance when limited to double-blind trials. Source: meta-analysis.
Follow the money without inventing a conspiracy
The available evidence establishes commercial concentration and an established reimbursement market. It does not by itself prove regulatory capture, fraudulent trials, or suppression of alternatives. Those allegations require contracts, funding disclosures, patents, lobbying records, and direct documentary evidence. The next reporting phase should trace clinical-trial sponsorship, ownership of manufacturing processes, medicinal-plant supply chains, and adverse-event oversight.
Safety must remain central: a Japanese review documented thousands of suspected adverse-event reports involving Kampo products, including lung and liver injury. Source: adverse-event study. Commercial success is not a substitute for transparent evidence.
Proposed documentary featured image: a photograph of a prescription Kampo preparation, by Shampoorobot, Wikimedia Commons, CC BY-SA 3.0. Original and license. Awaiting attachment.
