An infantile spasm is a brief seizure type that is characteristic of West syndrome. Many infants present with infantile spasms between 3-12 months of age. Early diagnosis and proper treatment of patients with infantile spasms can lead to improved clinical outcomes. However, proper identification of these patients using claims data with validation has not been performed. The authors developed and tested several algorithms using claims data. Claims data consisted of using International Classification of Disease (ICD), Current Procedural Terminology (CPT), and prescription codes. Access to the claims database was from an accountable care organization. The algorithm using the specific ICD code for infantile spasms only performed the best with high sensitivity and specificity. This algorithm can be used to perform additional research in claims data for patients with infantile spasms.