Always have a consultant by your skin's side. Equipped with a skin consultation LLM.

Yakuodo Co., Ltd. (Headquarters: Morioka City, Iwate Prefecture / President and CEO: Koichi Saigo / hereinafter referred to as Yakuodo), which operates 466 drugstores in the six prefectures of Tohoku, as well as Tochigi and Ibaraki Prefectures, will implement the fourth major renewal of its "Skin Diagnosis" function, integrated into the official Yakuodo app, starting Wednesday, July 1, 2026.

Yakuodo's concept is to replicate the "customer-centric customer service" cultivated over many years in stores within the app, and has been progressively evolving the skin diagnosis function. The first phase implemented an explanation function that learned from the knowledge of 100 staff members. The second phase involved a proprietary multi-recommendation function and a redesign of product categories. The third phase involved a shift to an AI specialized in skin diagnosis, achieving stable explanation quality.

- Renewal Highlights

1. New "Skin Consultation LLM" - Towards a place where you can consult about your skin anytime

The biggest change this time is the addition of the "Skin Consultation LLM," which allows users to consult about skin concerns anytime. From an icon constantly displayed at the bottom right of the app screen, users can freely ask questions and concerns about their skin condition and skincare.

Previous skin diagnoses primarily focused on understanding skin condition based on diagnostic results and checking explanations and recommended products. This renewal adds a new conversational interface to respond to the desire to "ask for more details" or "consult about skin concerns."

The Skin Consultation LLM further expands the diagnostic experience provided by the skin diagnosis-specialized AI revamped in the third phase. It evolves into an experience where users can not only receive diagnostic results but also confirm "what kind of care is suitable for my current skin" and "how to understand my skin concerns" through dialogue.

2. Added pre-skin diagnosis counseling - Diagnosis that considers "your skin's background"

A new counseling function has been added that can be answered before starting the skin diagnosis. Users can select answers from options regarding age, gender, items currently used for skincare, concerns about their skin condition, and concerns about their daily living environment.

Skin condition is deeply related not only to visible changes but also to daily skincare habits and living environments. For example, even with the same "concerned about dryness" result, the necessary advice will vary slightly depending on the items used and the living environment. This counseling function allows for a more detailed understanding of the user's situation before diagnosis, further personalizing the diagnostic results and explanations. It proposes solutions based not only on skin condition but also on daily lifestyle and care habits. This function naturally replicates the in-store counseling experience that Yakuodo values on the app.

3. Technical Initiatives - Beyond connecting to external LLMs, dialogue quality through in-house tuning

This Skin Consultation LLM is not simply an integration of existing chat AI, nor is it limited to API connections to external LLMs or prompt adjustments. Based on the skin diagnosis-specialized AI built in the third phase, and using an open-source large language model as a foundation, in-house tuning has been performed to achieve the conversational experience required for skin consultations.

Yakuodo's priority was not just to provide accurate information. It was to achieve "gentle, easy-to-understand, and supportive responses," similar to consulting with a staff member in-store. Based on the explanations from skin diagnoses and the expressions, phrasing, and response policies cultivated through in-store customer service, project members tuned the system to realize a consultation experience unique to Yakuodo. By stepping into the dialogue quality of the LLM itself, not just UI improvements, Yakuodo, as a retailer, aims to replicate "customer service that is close to local customers" digitally. This Skin Consultation LLM is a new technical challenge for that purpose.

- Future Developments

Through this fourth major renewal, the skin diagnosis function has moved from "diagnose and finish" to an experience of "consulting anytime." Yakuodo will continue to evolve in stages and further deepen the "counseling experience" within the app. Through the Skin Consultation LLM and the counseling function, Yakuodo aims to provide an experience where users can more easily consult about their skin and choose skincare with confidence. In-house staff will continue to be responsible for AI learning and improvement, and the system will continue to evolve based on customer feedback. As a community-based drugstore, Yakuodo aims to create services that are close to each customer's skin through both digital and real-world touchpoints.