Hyperhidrosis is a common condition that has a tremendous impact on the quality of life of patients. For moderate to severe hyperhidrosis, topical aluminum chloride hexahydrate (AC), iontophoresis, and botulinum toxin type A injections are first-line therapies. Botulinum toxin type A has been a useful addition to the hyperhidrosis armamentarium and typically is utilized when topical therapy or iontophoresis have failed. Although highly effective for most patients, there remains a subset of patients who do not completely respond to botulinum toxin type A injections. For these patients, combination therapy with AC can greatly improve patient response. We present a case series of 10 patients with hyperhidrosis and a history of partial response to botulinum toxin type A monotherapy. With the addition of AC 15% in a salicylic acid 2% gel base, 5 patients achieved 75% to 100% reduction in sweating and 5 patients achieved 100% reduction in sweating. Aluminum chloride hexahydrate in a salicylic acid gel base offers a novel and effective topical therapy in combination with botulinum toxin type A for patients with moderate to severe hyperhidrosis.