In the Heian period, an additional two facilities were built to the east and west of Heian-kyo, and they later became annexes of Seyaku-in Temple which had been built by Empress Komyo, and was under its control.
平安時代には、平安京の東西二カ所に増設され、同じく光明皇后によって設立された施薬院の別院となってその管理下におかれた。