Dandruff is a common condition characterized by white skin flakes throughout the hair. According to the Mayo Clinic, it can pop up for various reasons, including simple dry skin, sensitivity to hair products, fungal infection, and seborrheic dermatitis, which causes oily, irritated skin on the scalp. Dandruff shampoos use a variety of ingredients to combat these problems. Some contain antifungal agents, such as zinc pyrithione and ketoconazole, to kill the fungi that can cause dandruff and seborrehic dermatitis. Others combat skin flaking by slowing the rate at which skin cells die and peel off.
Because dandruff has different causes, you may need to try several different products before finding the one that does the best job of controlling your dandruff. If you've tried several over-the-counter shampoos and nothing seems to work, or if you have symptoms like intense scalp itching or burning, talk to a doctor; you may need a prescription-strength anti-dandruff shampoo, or possibly a steroid cream.
The dandruff shampoo that most consistently works for reviewers is Nizoral (Est. $16 for 7 oz.). Its main dandruff-fighting ingredient is ketoconazole, an antifungal medication that experts say often works when other treatments fail. Thousands of consumers at Amazon.com, Walmart.com and Walgreens.com consistently give Nizoral high overall ratings, saying it's very effective not just for dandruff but also for other skin conditions that affect the scalp, like eczema and psoriasis. Many users say they tried every dandruff product on the market, and Nizoral was the only one that worked for them. And, in addition to clearing up dandruff, users say this shampoo lathers nicely, is easy to spread, and generally does a good job getting the hair and scalp clean.
As a bonus, some users say that since they started using Nizoral, their hair has actually become thicker and stronger. Nizoral does have its disadvantages, however. For a start, it's much more expensive than most dandruff shampoos on the market. Also, many reviewers say it has an unpleasant, medicinal smell, and some complain that it's harsh and drying to the hair; however, because it's designed to be used once or twice per week, in between regular shampooing, users can continue to use other hair products to combat dry or frizzy hair on the days they don't use Nizoral. Some users also worry about the safety of the powerful antifungal agent in Nizoral, though expert feedback indicates that used topically, ketoconazole is relatively safe. In any event, most are happily willing to deal with those tradeoffs in exchange for an effective dandruff treatment.
However, for those who don't want to pull out the big guns right away, there are other dandruff shampoos on the market that are less powerful, but also less expensive. One of the best known is Head & Shoulders Clinical Strength Dandruff and Seborrheic Dermatitis Shampoo (Est. $14 for two 13.5 oz. bottles), which earns high ratings in hundreds of reviews on sites like Amazon.com, Walmart.com and Walgreens.com. This shampoo's formulation combats not only dandruff but also seborrheic dermatitis, helping to prevent itching, redness, and irritation as well as the flaking and scaling caused by these conditions.
Reviewers are split on the scent of Head & Shoulders Clinical Strength; some love it, while others say it has a strong, medicinal scent, something that's common to most clinical-strength dandruff shampoos. One thing the majority of reviewers do agree on is how well it works. Many reviewers say they experienced a noticeable difference in dandruff flakes after using this shampoo for just two days, with other symptoms such as redness and itching dissipating after three or so days of use. Many users say it eliminated their dandruff and dermatitis, as well as the associated symptoms, after a few weeks. Users also appreciate Head & Shoulders' pH-balanced formula, which is gentle enough for everyday use without drying the hair or scalp. Although selenium sulfide, the active ingredient in Head & Shoulders, isn't as consistently effective as ketoconazole, it works for many users and costs much less.
If neither Head & Shoulders nor Nizoral works for you, one product that might offer relief is Neutrogena T/Gel Dandruff Shampoo, Original (Est. $12 for 16 oz.). Neutrogena contains coal tar, which combats skin flaking by slowing the turnover rate of skin cells, as well as salicylic acid to help balance the scalp and remove sebum and other buildup that can contribute to flaking. Editors at InStyle magazine name Neutrogena T/Gel the best dandruff shampoo in their annual best beauty buys roundup for 2016, noting that it treats scalp concerns effectively while leaving users with shiny, manageable hair.
Users at Amazon.com and Walgreens.com say this product is very effective against dandruff and eczema, even when every other product – including Nizoral – has failed. On the downside, users consistently find that this shampoo smells terrible – reviews compare it to motor oil, mothballs, and burning rubber – and, contrary to InStyle's opinion, that it can be very harsh and drying. In addition to the original formula, Neutrogena offers an extra-strength formula, Neutrogena T/Gel Therapeutic Shampoo – Extra Strength (Est. $10 for 6 oz.), Neutrogena T/Gel Therapeutic Shampoo - Stubborn Itch (Est. $13 for 6 oz.) for people with persistent itching, and a formula specially designed to combat scalp build-up, Neutrogena T/Gel Therapeutic Shampoo - Scalp Build-Up Control (Est. $9 for 4.5 oz.), as well as a shampoo and conditioner in-one and a stand-alone conditioner.