Scientific Review Identifies Selenium Sulfide and Zinc Pyrithione as Evidence-Based Dandruff Treatments
Scientists from Head & Shoulders and dermatology experts reviewed the latest clinical evidence on dandruff treatment during the September 2026 Science of Skin Summit in Austin, Texas, highlighting the importance of looking beyond antifungal activity alone when evaluating over-the-counter (OTC) dandruff shampoos.
According to the review presented at the summit, effective dandruff management involves several aspects of scalp health, including controlling visible flaking, addressing scalp irritation and supporting the scalp barrier. The researchers said these factors may be important for achieving sustained control of a condition that commonly returns after treatment.
The review examined evidence surrounding two established OTC active ingredients, selenium sulfide and zinc pyrithione. The available clinical data discussed by the researchers suggest that a well-formulated shampoo containing 1% selenium sulfide has a strong evidence base when maximum OTC dandruff control is the primary objective. At the same time, formulations containing 1% zinc pyrithione, particularly when combined with ingredients intended to support the scalp barrier and address oxidative stress, have demonstrated benefits relevant to longer-term scalp care.
Head & Shoulders said these findings support the approach behind its proprietary shampoo collections, which are designed to address dandruff through multiple dimensions of scalp care. The company points to its selenium sulfide and zinc pyrithione formulations, including products incorporating its HydraZinc technology, as examples of formulations designed for both dandruff control and ongoing scalp health.
Dr. Divya Shokeen, a board-certified dermatologist and hair transplant surgeon, said treatments that address multiple aspects of scalp health and irritation may offer advantages over approaches focused solely on antifungal activity.
“When considering currently available OTC evidence, a well-formulated product with 1% selenium sulfide has the strongest efficacy data for maximum dandruff control, while zinc pyrithione demonstrates important benefits in reducing scalp irritation and maintaining scalp health over time,” Shokeen said.
Dandruff Involves More Than Visible Flakes
Dandruff is commonly recognized by white or yellowish flakes appearing on the scalp and hair. However, emerging research suggests that the condition involves a more complex interaction among the scalp microbiome, skin-barrier function, irritation and inflammation.
A Viewpoint article published in JAMA Dermatology in August 2026 discussed the relationship between microbiome imbalance, barrier dysfunction and inflammatory processes in dandruff and seborrheic dermatitis. The broader research landscape indicates that scalp flaking should not necessarily be considered an isolated symptom.
The scalp’s barrier plays an important role in maintaining hydration and protecting underlying skin from environmental stressors. When barrier function is disrupted, irritation and sensitivity can increase, potentially contributing to an ongoing cycle of scalp discomfort and visible symptoms.
Oxidative stress and inflammation are also being investigated as components of scalp health. As a result, researchers are increasingly considering whether dandruff products should provide benefits beyond suppressing the microorganisms associated with the condition.
Both selenium sulfide and zinc pyrithione have demonstrated antifungal activity in clinical studies. Research has also reported reductions in scalp irritation and improvements in measures of scalp health with products containing these ingredients.
Clinical Evidence for 1% Selenium Sulfide
The evidence reviewed at the Science of Skin Summit included randomized clinical studies evaluating selenium sulfide and ketoconazole formulations.
One randomized, double-blind study involving 350 participants compared a tested 1% selenium sulfide shampoo with a tested 2% ketoconazole shampoo. According to the reviewed findings, the selenium sulfide formulation produced greater reductions in adherent scalp flaking after four and six weeks of treatment.
The evidence also includes studies examining different concentrations of ketoconazole. In a separate randomized trial involving people with severe dandruff or seborrheic dermatitis, 2% ketoconazole was reported to reduce flaking severity more effectively than 1% ketoconazole.
However, the review emphasizes an important limitation when making direct comparisons. No identified published study directly compared 1% selenium sulfide with 1% ketoconazole under identical study conditions. Therefore, conclusions regarding comparative efficacy between those two specific concentrations should be interpreted in the context of the available evidence rather than as the result of a head-to-head clinical trial.
Additional clinical research has found that an OTC selenium sulfide shampoo can provide efficacy comparable to prescription-strength ketoconazole for reducing scaling and irritation severity.
Taken together, the studies reviewed by the researchers support 1% selenium sulfide as a well-supported OTC option when the principal goal is achieving substantial control of dandruff symptoms. Head & Shoulders markets its Clinical Strength product as a selenium sulfide-based option for consumers seeking OTC dandruff treatment.
Zinc Pyrithione and Long-Term Dandruff Management
While short-term symptom reduction is an important consideration, dandruff is typically a recurring condition. This means that long-term treatment and consistent use can be important components of management.
Clinical evidence reviewed by the researchers includes a 48-week randomized controlled study of a 1% zinc pyrithione shampoo. The study found that the formulation maintained significant efficacy compared with placebo throughout the study period, with no evidence that its effectiveness diminished over time.
Other research has reported benefits associated with zinc pyrithione formulations in measures related to scalp barrier quality and scalp health biomarkers.
These findings are relevant because successful management of a recurring condition often depends not only on the initial reduction of flakes but also on continued control during routine use.
Dr. KC Locker, senior scientist at Head & Shoulders, emphasized the importance of evaluating complete products rather than considering individual active ingredients separately.
“The best dandruff shampoo is one that people will use consistently over time,” Locker said. He added that comprehensive scalp treatment and a product experience that encourages continued use are important considerations in ongoing dandruff management.
Head & Shoulders has also introduced its patent-pending HydraZinc technology in certain products. The company describes the technology as part of its approach to combining zinc pyrithione with ingredients intended to support scalp hydration and barrier health.
The evidence reviewed by the company and dermatology experts points toward a broader way of evaluating dandruff treatments. Antifungal activity remains an important part of dandruff management, but researchers are also examining how formulations influence irritation, hydration, barrier function and the recurrence of symptoms.
This distinction is particularly relevant when comparing products that contain the same active ingredient. The overall formulation can influence factors such as how the product interacts with the scalp, its tolerability and whether consumers are able to use it consistently.
Consequently, the researchers said consumers should consider the complete formulation and available clinical evidence rather than evaluating a shampoo solely according to the concentration or identity of its active ingredient.
For people primarily seeking maximum OTC dandruff control, the evidence reviewed supports consideration of a well-formulated 1% selenium sulfide shampoo. For longer-term scalp maintenance, clinical research on zinc pyrithione has demonstrated sustained dandruff-control benefits, along with findings related to scalp irritation and barrier health.
What Consumers Should Consider
The findings presented at the September 2026 summit provide several considerations for consumers selecting an OTC dandruff shampoo.
Maximum dandruff control: The available evidence reviewed by the researchers supports well-formulated 1% selenium sulfide shampoos as an OTC option with strong clinical evidence for reducing dandruff. Head & Shoulders Clinical Strength is one example of a selenium sulfide-containing product.
Long-term management: Because dandruff can recur, sustained treatment may be important. Clinical studies involving 1% zinc pyrithione have demonstrated continued efficacy over extended periods, including a 48-week randomized controlled study.
Scalp health: Visible flakes are only one aspect of dandruff. Consumers may also consider formulations designed to address scalp irritation, hydration and barrier function as part of ongoing scalp care.
Complete formulation: The clinical performance of a shampoo depends on the formulation as a whole, not necessarily on its active ingredient in isolation. Product tolerability and the ability to use a treatment consistently are also relevant to real-world outcomes.
Following directions: Consumers should use OTC dandruff products according to their labeling and directions for use. Consistent application is an important part of maintaining symptom control.
The evidence review ultimately underscores that dandruff treatment can involve more than simply reducing visible flakes. Research into the scalp microbiome, barrier integrity, irritation and inflammation is expanding the understanding of how dandruff develops and persists.
For consumers, the available evidence provides support for different approaches depending on the treatment objective. Selenium sulfide has substantial evidence supporting its use for strong OTC dandruff control, while zinc pyrithione has demonstrated sustained performance in longer-term studies and has been associated with measures of scalp health.
Consumers should consult a healthcare professional if dandruff is severe, persistent, significantly inflamed, associated with other concerning symptoms, or does not improve with appropriate OTC treatment. A healthcare professional can determine whether the symptoms are consistent with dandruff or another scalp condition and recommend an appropriate treatment approach.
About Head & Shoulders
With more than 60 years of trailblazing innovation in scalp care, Head & Shoulders is the world’s #1 anti-dandruff shampoo, #1 dermatologist-recommended anti-dandruff brand, and the most-awarded scalp care brand** with a broad portfolio of products with cosmetic benefits and solutions for different hair types and scalp concerns. For more information, visit www.headandshoulders.com or follow Head & Shoulders on Instagram, TikTok and Facebook.
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