This case report chronicles the clinical presentation and unusual response to treatment of a patient with rapid gingival recession and dental erosion secondary to local cocaine application. The initial clinical diagnosis was necrotizing ulcerative periodontitis; only after several years of therapy did the patient voluntarily inform one of the therapists that cocaine had been regularly applied to the affected gingival sites. This case illustrates the importance of including cocaine application to gingival tissues in a differential diagnosis in cases of rapid gingival recession and dental erosion of unknown etiology.