Herein, we described a 24-year-old proband with moderate DD/ID, language delay, cryptorchidism, hypotonia, behavioral abnormalities, sexual dysfunction, dense hair, craniofacial anomalies, allergic purpura and eczema, and drug allergies caused by a novel de novo splicing variant, c.1496 + 1G > T, in the SMARCC2 gene. Here, SMARCC2 is linked to drug allergy.