Radiation somnolence syndrome.

Although initially described 7 decades ago, somnolence syndrome remains a poorly understood subacute effect of cranial irradiation. Despite the relatively transient and benign nature of somnolence syndrome, its symptoms can be distressing for children and caregivers. Anticipatory guidance related to radiation-induced somnolence remains a critical nursing intervention. This article reviews what is known about somnolence syndrome, including its causes, symptoms, and management.