BackgroundMelatonin is commonly used to treat sleep disturbance in children and adolescents, although uncertainties about its optimal use remain.ObjectiveTo determine to what extent prescribing of melatonin complies with evidence-based clinical practice standards.MethodsAs part of a quality improvement programme, the Prescribing Observatory for Mental Health conducted a retrospective clinical audit in UK services for children and adolescents.FindingsData were submitted for 4151 children and adolescents up to 18 years of age, treated with melatonin: 3053 (74%) had a diagnosis of neurodevelopmental disorder. In 2655 (73%) of the 3651 patients prescribed melatonin to be taken regularly, the main reason was to reduce sleep latency (time taken to fall asleep). In 409 patients recently starting melatonin, a non-pharmacological intervention had already been tried in 279 (68%). The therapeutic response of patients early in treatment (n=899) and on long-term treatment (n=2353) had been assessed and quantified in 36% and 31%, respectively, while for review of side effects, the respective proportions were 46% and 43%. Planned treatment breaks were documented in 317 (13%) of those on long-term treatment.ConclusionsMelatonin was predominantly prescribed for evidence-based clinical indications, but the clinical review and monitoring of this treatment fell short of best practice.Clinical implicationsWith limited methodical review of melatonin use in their patients, clinicians will fail to garner reliable information on its risks and benefits for individual patients. The lack of such practice-based evidence may increase the risk of melatonin being inappropriately targeted or continued despite being ineffective or no longer indicated.