SZRT is a combination of Semen Zizyphi Spinosae (Suanzaoren), Sclerotium Poriae Cocos (Fuling), Radix Ligustici Chuanxiong (Chuanxiong), Rhizoma Anemarrhena (Zhimu), and Radix Glycyrrhizae (Gancao). It was the most commonly prescribed Chinese herbal formula used for the treatment of insomnia. In the classical literature and previous studies, SZRT was said to calm the nerves and nourish the blood to eventually bring on a tranquillizing sensation and improved the quality of sleep without generating significant side effects. In order to evaluate the efficacy of SZRT for sleep disturbance during methadone maintenance, investigators designed a randomized, double-blind, placebo-controlled trial and perform the proteomic-system biology analysis to find the biomarker associated with sleep condition.