Dry Derma Relief (Si Wu Xiao Feng Yin) is directly based upon Si Wu Xiao Feng Yin (Four Materials Eliminate Wind Decoction), first described by Wu Qian in Golden Mirror of the Medical Tradition in 1742. The formula addresses Wind Heat invasions targeting the skin with concurrent Blood deficiency.

Dry Derma Relief is most commonly given to dogs because of their apparent predisposition to Blood deficiency. The formula has a slightly increased content of Wind- dispersing herbs relative to Blood tonics from those found in the original classical formula. Bupleurum root helps to mobilize the stagnant Liver Qi secondary to Liver Blood deficiency while expelling Wind Heat invasions. Dictamnus root, Chinese mint herb, Schizonepeta herb, Siler root and Pubescent angelica root all expel Wind invasion.

The Blood tonics in this formula are those found in Four Substances (Si Wu Tang), the quintessential Blood tonic formula. Historically, the herbs making up Four Substances are raw Rehmannia root, Dong quai root, Chinese white peony root and Sichuan lovage rhizome. Chinese red peony root is used here in place of Chinese white peony root to provide added Blood-cooling effects. Red jujube fruit has been added to provide more Blood-tonifying effects.