Introduction: Gingival overgrowth, a known side effect of calcium channel blockers, particularly nifedipine, usually presents as a diffuse overgrowth. An unusual presentation of amlodipine-induced gingival overgrowth is presented here, with a large, erythematous gingival mass as the most prominent feature, and rapid, almost complete resolution of the mass after reduction of amlodipine dosage. Case Presentation: A boy, aged 7 years, presented with a gingival mass first noticed a week previously, with no associated discomfort or bleeding. His medical history was significant for Wiskott-Aldrich syndrome, bone marrow transplant 5 years previously, and subsequent development of severe chronic graft-versus-host-disease. Hismedication included: 1) amlodipine; 2) enalapril; 3) tacrolimus; 4) sulfamethoxazole/trimethoprim; 5) voriconazole; 6) hydrocortisone cream; and 7) intravenous immunoglobulin infusions. Allergies included: 1) vancomycin; 2) metoclopramide; 3) clonidine; and 4) latex. Examination revealed mild generalized gingival overgrowth and the presence of a large, erythematous, sessile, soft, non-tender mass on the mandibular right gingiva between the primary lateral incisor and canine, resembling a pyogenic granuloma. No suppuration, bleeding on probing, or radiographic abnormalities were noted. A recommendation was made to the physician of the patient to replace amlodipine with a different class of antihypertensive. In response, amlodipine dosage was decreased by 50% to 2.5 mg daily. At a 2-week follow-up visit, considerable reduction in size of the gingival mass had occurred, and shortly after complete resolution was reported by his parents. No other intervention, such as scaling or excision, had been performed. Conclusion: Discontinuation or reduction of the amlodipine dose to < 5 mg daily prior to any surgical intervention should be considered in patients taking amlodipine presenting with a gingival mass.