Allergic contact dermatitis is a chronic inflammatory T cell mediated disease that can be recalcitrant to existing treatments. Ustekinumab is a monocloncal antibody blocking IL-12 and IL-23, shown to be effective and safe for patients with psoriasis. Despite both IL-12 and IL-23 involvement in contact allergy, the effect of Ustekinumab on allergic contact dermatitis has not been reported.