In this study, the investigator plans a randomized trial of melatonin versus placebo post acute pediatric concussion. The investigator hypothesizes that patients with acute concussions managed with melatonin will have improved sleep, decreased depressive symptoms, decreased risk of prolonged concussion symptoms and faster resolution of concussion symptoms.

To compare the risk of persistent post-concussive symptoms (PPCS) between melatonin and placebo after an acute pediatric concussion.

To determine if melatonin compared to placebo reduces the risk of PPCS for pediatric patients.

This is a prospective single-blinded randomized control trial of pediatric patients in the emergency department (ED) diagnosed with an acute concussion. Patients 12-18 years old with an acute concussion diagnosis will be eligible. All participants will receive actigraphy watches to wear on their wrists and measure sleep and activity patterns. Participants in the melatonin group will be instructed to take 3 mg of liquid melatonin 1 hour prior to their habitual fall asleep time daily for 30 days. Participants in the placebo group will be instructed to take their placebo liquid 1/2 hour prior to their habitual fall asleep time daily for 30 days.

All participants will be given standardized weekly assessments to track their concussion, sleep and depressive symptoms for one month. Research assistants will also arrange follow up in the telemedicine neurology headache clinic within 4 weeks post injury. At the follow-up visit, subjects will complete the Post Concussion Symptom Inventory (PCSI), Pediatric Sleep Disturbance (PSD), and Revised Childhood Anxiety and Depression Scales (RCADS).

Inclusion Criteria:

• Patient diagnosed with an acute concussion within 72 hours
• Patient greater than 8 and less than 19 years old

Exclusion Criteria:

• Currently taking psychiatric medication
• Cognitive delay
• Glasgow Coma Score < 14
• positive findings on head computed tomography
• Any patient with intracranial surgery, pathology or instrumentation (e.g. ventriculoperitoneal shunt, brain tumor etc)
• Use of melatonin within the last week

For the study, researchers will collect the age, sex, past medical history and through surveys, past, present and future symptoms after a head injury. This information will be used to determine which age groups are at risk and which constellation of symptoms persist following an acute head injury. All research documents and protected health information will be kept in a locked cabinet and a password protected RedCap database that only study staff personnel have access to. No data will be shared until manuscript is written, but will only be shared in manuscript and not in individual data. If significant adverse data is found for a patient, the Lead principal investigator will discuss with the subject and primary care physician.