Parasomnias are a group of sleep disorders that involve undesirable physical events or experiences that occur while falling asleep, during sleep, or while waking up from sleep. Parasomnias may be classified by sleep state. Some such as sleepwalking, sleeptalking, confusional arousals, and night terrors may occur in non-rapid eye movement (NREM) sleep. Others such as nightmares and REM-behavior disorder occur in rapid eye movement (REM) sleep. These events are most common in young children and gradually decrease in frequency over time. Healthy children that present with parasomnias only require a focused sleep history and physical exam for diagnosis. In most cases, treatment is usually not necessary. You may need to take safety precautions to protect the child during these episodes. Medication is prescribed in some cases if the parasomnias are frequent or having a negative impact in a child's daily activities.