Three patients with dystrophic epidermolysis bullosa (DEB) were treated with vitamin E, with the result that bullae formation ceased. Measurement of collagenase activity in the blister areas revealed a reversion to normal collagenase activity after 30 days of vitamin E therapy. These findings tend to support the theory that DEB is influenced by the increase in the level of skin collagenase, and the increased collagenase activity directly influences blister formation.