Based on the ancient doctrine of 痹证 bì zhèng, or obstruction, there is a saying 不 痛 止 痛. 痛 止 不 痛 BU TONG ZHI TONG, TONG ZHI BU TONG
which translates as when there is no obstruction there is no pain, when there is pain there is obstruction.

Da Zhi Tong Tang was made to eliminate blockages therefore relieving pain, not just blunting the pain response.