Excessive sleepiness is not a disorder in itself. It is a symptom that can have many different causes. The common causes are poor sleep habits, an irregular sleep schedule, a sleep disorder like obstructive sleep apnea, side effects from certain medications, and other underlying medical conditions, such as narcolepsy or idiopathic hypersomnolence. Once your child’s doctor has determined the cause of the excessive sleepiness, you can create a treatment plan together. For some children, that involves changing sleep habits and improving behaviors and elements of the sleep environment. For others, further medical tests or sleep studies may be indicated. Many of these problems may be evaluated with a polysomnogram to rule out other sleep problems. A multiple sleep latency test (MSLT) may be required to assess sleepiness and aid in the diagnosis. Treatments may consist of individualized medication management, scheduled naps and modifications of work/school schedules.