Parasomnias are common in childhood but there is no established treatment for parasomnias. The aim of this study was to (1) report on the outcome of using L-tryptophan to manage parasomnias in children and (2) examine sleep architecture and subjective psychological/sleep symptoms in children with parasomnia. A retrospective analysis was conducted of charts of children (3-18 years old) who underwent polysomnographic testing and were diagnosed with primary parasomnia. Study patients were either prescribed L-tryptophan (daily dose range: 500-4500 mg, mean dose of 2400 mg) to manage their parasomnias or administered no treatment whereby parents/guardians declined treatment. Questionnaires assessing sleep and psychosocial symptoms were administered at the initial clinical consultation and a follow-up parasomnia outcome questionnaire was administered over the phone to parents/guardians. One hundred and sixty-five children (106 boys, 59 girls) received a sleep diagnosis of primary parasomnia. A significantly (p < 0.001) higher proportion (84%) of children taking L-tryptophan experienced improvements in their parasomnia symptoms compared with those (47%) who chose not to use L-tryptophan. Polysomnography revealed that children with parasomnias had an altered sleep architecture based on age-related normative values. Children with a diagnosis of parasomnia were also subjectively more fatigued and endorsed more depressive symptoms. This study finds that parasomnias in children are not benign and that treatment with L-tryptophan provides a favorable outcome. Children diagnosed with parasomnia had altered sleep architecture, were more fatigued, and endorsed depressive symptoms. This study supports the need to diagnose and treat parasomnias in children.