Background/Aim: Dandruff is a common scalp problem associated with flaky and inflamed skin. In this study, we investigated the efficacy of a shampoo containing piroctone olamine and climbazole and the combination of this shampoo with a scalp tonic containing piroctone olamine and licochalcone A, derived from Glycyrrhiza inflata root extract, to reduce dandruff. Study Design/Methods: After conditioning, 102 subjects (♂ 56 and 46 ♀) with moderate to very strong dandruff affection underwent a randomized half head study for 4 weeks. The volunteers’ heads were washed regularly either with a placebo or the anti-dandruff shampoo, followed by the anti-dandruff tonic application or no treatment. In a 2-week post-treatment phase, subjects only applied placebo shampoo. Every two weeks, trained experts assessed dandruff affection based on a scale of 1 to 6. At study start and after every 2 weeks, cytokine concentrations and anti-fungal activity of test products were determined in scalp wash-ups by enzyme-linked immunosorbant assays or a Malassezia colony-forming assay, respectively. Results: Results of expert grading and anti-fungal activity revealed a significant reduction in dandruff affection and Malassezia colony-forming units after treatment with the anti-dandruff shampoo or its combination with the tonic. Dandruff affection even remained reduced in the post-treatment phase when levels of Malassezia colony-forming units had returned to baseline. Cytokine analyses proved a significant decrease in pro-inflammatory dandruff markers after treatment with both anti-dandruff products. For the shampoo/tonic combination, a superior reduction of one scalp inflammatory marker was determined even after the post-treatment phase. Conclusion: Both the rinse-off shampoo as well as its combination with the leave-on tonic excellently alleviated dandruff and its associated micro-inflammation. Both treatments showed anti-fungal activity. The superior benefit, exerted by the combination, is primarily based on the known anti-inflammatory effect of licochalcone A and the improved scalp substantivity of the leave-on application.
 J. R. Schwartz, C. M. Cardin and T. L. Dawson, “Dandruff and Seborrheic Dermatitis,” In: R. Baran and H. I. Maibach, Eds, Textbook of Cosmetic Dermatology, Martin Dunitz Ltd., London, 2004, pp. 259-272.
 L. Misery, V. Sibaud, M. Ambronati, G. Macy, S. Boussetta and C. Taieb, “Sensitive Scalp: Does This Condition Exist? An Epidemiological Study,” Contact Dermatitis, Vol. 58, No. 4, 2008, pp. 234-238. doi:10.1111/j.1600-0536.2007.01288.x
 J. C. Szepietowski, A. Reich, E. Wesolowska-Szepietowska and E. Baran, “Quality of Life in Patients Suffering from Seborrheic Dermatitis: Influence of Age, Gender and Education Level,” Mycoses, Vol. 52, No. 4, 2009, pp. 357-363. doi:10.1111/j.1439-0507.2008.01624.x
 B. I. Ro and T. L. Dawson, “The Role of Sebaceous Gland Activity and Scalp Microfloral Metabolism in the Etiology of Seborrheic Dermatitis and Dandruff,” Journal of Investigative Dermatology Symposium, Vol. 10, No. 3, 2005, pp. 194-197.
 K. Kerr, T. Darcy, J. Henry, H. Mizoguchi, J. R. Schwartz, S. Morrall, et al., “Epidermal Changes Associated with Symptomatic Resolution of Dandruff: Biomarkers of Scalp Health,” International Journal of Dermatology, Vol. 50, No. 1, 2011, pp. 102-113. doi:10.1111/j.1365-4632.2010.04629.x
 S. Seité, J. Paries, P. Reygagne, Z. Hamidou, C. Jouanique, G. Perez-Pala, et al., “A Lipohydroxyacid-Containing Shampoo Improves Scalp Condition and Quality of Life in Patients with Seborrheic Dermatitis and Light-to-moderate Scalp Psoriasis," Journal of Cosmetic Dermatology, Vol. 8, No. 2, 2009, pp. 108-113. doi:10.1111/j.1473-2165.2009.00431.x
 G. Freitag and T. Hoppner, “Results of a Postmarketing Drug Monitoring Survey with a Polidocanol-urea Preparation for Dry, Itching Skin,” Current Medical Research and Opinion, Vol. 13, No. 9, 1997, pp. 529-537. doi:10.1185/03007999709113326
 I. Furuhashi, S. Iwata, S. Shibata, T. Sato and H. Inoue, “Inhibition by Licochalcone A, a Novel Flavonoid Isolated from Liquorice Root, of IL-1beta-induced PGE2 Production in Human Skin Fibroblasts,” Journal of Pharmacy and Pharmacology, Vol. 57, No. 12, 2005, pp. 1661-1666. doi:10.1211/jpp.57.12.0017
 L. Kolbe, J. Immeyer, J. Batzer, U. Wensorra, K. tom Dieck, C. Mundt, et al., “Anti-inflammatory Efficacy of Licochalcone A: Correlation of Clinical Potency and in Vitro Effects,” Archives of Dermatological Research, Vol. 298, No. 1, 2006, pp. 23-30. doi:10.1007/s00403-006-0654-4
 T. M. Weber, R. I. Ceilley, A. Buerger, L. Kolbe, N. S. Trookman, R. L. Rizer, et al., “Skin Tolerance, Efficacy, and Quality of Life of Patients with Red Facial Skin Using a Skin Care Regimen Containing Licochalcone A,” Journal of Cosmetic Dermatology, Vol. 5, No. 3, 2006, pp. 227-232. doi:10.1111/j.1473-2165.2006.00261.x
 D. Schweiger, C. Baufeld, P. Drescher, B. Oltrogge, S. Hopfner, J.-P. Vietzke, et al., “Efficacy of a New Tonic Containing Urea, Lactate, Polidocanol and Glycyrrhiza Inflata Root Extract against Symptoms of a Dry, Itchy and Subclinically Inflamed Scalp,” Skin Pharmacology and Physiology, 2013 (unpublished).
 G. A. Turner, M. Hoptroff and C. R. Harding, “Stratum Corneum Dysfunction in Dandruff,” International Journal of Cosmetic Science, Vol. 34, No. 4, 2012, pp. 298-306. doi:10.1111/j.1468-2494.2012.00723.x
 P. Mayser, P. Haze, C. Papavassilis, M. Pickel, K. Gruender and E. Guého, “Differentiation of Malassezia Species: Selectivity of Cremophor EL, Castor Oil and Ricinoleic Acid for M. Furfur,” British Journal of Dermatology, Vol. 137, No. 2. 1997, pp. 208-213. doi:10.1046/j.1365-2133.1997.18071890.x
 J. R. Schwartz, R. Shah, H. Krigbaum, J. Sacha, A. Vogt and U. Blume-Peytavi, “New Insights on Dandruff/Seborrhoeic Dermatitis: The Role of the Scalp Follicular Infundibulum in Effective Treatment Strategies,” British Journal of Dermatology, Vol. 165, Suppl. 2, 2011, pp. 18-23. doi:10.1111/j.1365-2133.2011.10573.x
 M. Loden, “Role of Topical Emollients and Moisturizers in the Treatment of Dry Skin Barrier Disorders,” American Journal of Clinical Dermatology, Vol. 4, No. 11, 2003, pp. 771-788. doi:10.2165/00128071-200304110-00005
 W. Wigger-Alberti, K. Kluge and P. Elsner, “Clinical Effectiveness and Tolerance of Climbazole Containing Dandruff Shampoo in Patients with Seborrheic Scalp Eczema,” Praxis, Vol. 90, No. 33, 2001, pp. 1346-1349.
 T. Schmidt-Rose, S. Braren, H. Folster, T. Hillemann, B. Oltrogge, P. Philipp, et al., “Efficacy of a Piroctone Olamine/Climbazol Shampoo in Comparison with a Zinc Pyrithione Shampoo in Subjects with Moderate to Severe Dandruff,” International Journal of Cosmetic Science, Vol. 33, No. 3, 2011, pp. 276-282. doi:10.1111/j.1468-2494.2010.00623.x
 T. Terui, T. Hirao, Y. Sato, T. Uesugi, M. Honda, M. Iguchi, et al., “An Increased Ratio of Interleukin-1 Receptor Antagonist to Interleukin-1alpha in Inflammatory Skin Diseases,” Experimental Dermatology, Vol. 7, No. 6, 1998, pp. 327-334. doi:10.1111/j.1600-0625.1998.tb00332.x
 O. Arican, M. Aral, S. Sasmaz and P. Ciragil, “Serum Levels of TNF-Alpha, IFN-Gamma, IL-6, IL-8, IL-12, IL-17, and IL-18 in Patients with Active Psoriasis and Correlation with Disease Severity,” Mediators of Inflammation, Vol. 5, No. 5, 2005, pp. 273-279. doi:10.1155/MI.2005.273
 M. A. Perkins, C. W. Cardin, M. A. Osterhues and M. K. Robinson,” A Non-invasive Tape Absorption Method for Recovery of Inflammatory Mediators to Differentiate Normal from Compromised Scalp Conditions,” Skin Research and Technology, Vol. 8, No. 3, 2002, pp. 187-193. doi:10.1034/j.1600-0846.2002.20337.x
 K. J. Mills, P. Hu, J. Henry, M. Tamura, P. Tiesman and J. Xu, “Dandruff/Seborrhoeic Dermatitis is Characterized by an Inflammatory Genomic Signature and Possible Immune Dysfunction: Transcriptional Analysis of the Condition and Treatment Effects of Zinc Pyrithione,” British Journal of Dermatology, Vol. 166, Suppl. 2, 2012, pp. 33-40. doi:10.1111/j.1365-2133.2012.10863.x