Monosymptomatic nocturnal enuresis (MNE) is a common pediatric developmental disorder. MNE refers to urinary incontinence in the sleep state in children aged ≥5 years, without other LUT symptoms, and without bladder dysfunction. Its pathogenesis mainly include overnight polyuria, overactive bladder, sleep-arousal dysfunction, genetics, and abnormal secretion of anti-diuretic hormone (ADH). Desmopressin is a synthetic analog of ADH arginine-vasopressin (AVP), which is used to treat central diabetes insipidus and primary nocturnal enuresis (PNE). Desmopressin decreases urine production at night when taken at bedtime. Insufficient ADH secretion at night will contribute to nocturnal polyuria, which is an important cause of NE. Therefore, desmopressin, a synthetic analog of ADH, is frequently used for NE and is an evidence-based therapy (grade ⅠA evidence). Some children, however, have desmopressin resistance and do not achieve the desired treatment goals. What's more,there's a high relapse rate of desmopressin after withdrawing. Suoquan mixture is a Chinese medicine commonly used to treat NE in children. It is composed of Cuscuta, Codonopsis, Psoralea corylifolia Linn ,Astragalus,mantis egg-case and ephedra. It has not only a certain cure rate but also has a lower relapse rate . However there's few evidence could prove that. In this study,the investigators compared the 3 month treatment response and relapse rate (RR) in the following 6 months of desmopressin and desmopressin plus suoquan, and observe if there will be a lower relapse rare in desmopressin plus Suoquan. Moreover, the investigators will try to explore the mechanism of Suoquan mixture in MNE.

Inclusion Criteria:

• bedwetting occured ≥2nights/week,last for at least 3 months
• without other LUT symptoms
• without bladder dysfunction.
• no treatment in last 3 months
• signed the consent

Exclusion Criteria:

• had other LUT symptoms
• with bladder dysfunction
• had treatment in last 3 months
• without the consent