Aquagenic keratoderma (AK) is a rare acquired skin condition characterized by recurrent and transient white papules and plaques associated with a burning sensation, pain, pruritus and/or hyperhidrosis on the palms and more rarely, soles triggered by sweat or contact with water. Often AK cause significant discomfort, thus requiring an appropriate therapy. Topical aluminum-based products are the most commonly used medications, but they are not always effective. We report a case of AK unresponsive to topical 20% of aluminum chloride successfully treated with tap water iontophoresis.