Ketoconazole shampoo is a medicated shampoo designed to treat fungal infections affecting the scalp. You can use it for conditions like stubborn dandruff, psoriasis, and more. Shampoos containing ketoconazole are available both over the counter (OTC) and by prescription from your doctor.

Ketoconazole shampoo is commonly advertised as a dandruff treatment, with OTC brands like Nizoral available in supermarkets or online for purchase. Dry scalp causes some dandruff, while other dandruff is actually seborrheic dermatitis. Seborrheic dermatitis may be associated with an overgrowth of Malassezia, a yeast fungus that’s naturally present on your skin. Ketoconazole can help treat dandruff by reducing the fungus and inflammation.

Psoriasis

Ketoconazole is a common treatment for psoriasis, another inflammatory skin disease that causes skin flaking, skin plaques, and redness. Yeast-like fungus often infects these skin plaques. Prescription ketoconazole may be needed for psoriasis flares.

Tinea infections

Ketoconazole shampoo can also treat tinea capitis and tinea versicolor. Tinea capitis is a superficial, ringworm-like fungus infection that affects the scalp. Tinea versicolor is a skin infection that’s caused by an overgrowth of a type of yeast that naturally lives on your skin.

Hair loss

While ketoconazole is most frequently used for its antifungal properties to treat infections or conditions like seborrheic dermatitis, there is anecdotal evidence indicating that it may also help promote hair growth or reduce hair loss. One small pilot study consisting of 15 people with alopecia, for example, found that ketoconazole may be able to improve hair regrowth.

Different types of ketoconazole shampoos are available OTC and by prescription from a healthcare provider.

OTC ketoconazole shampoos contain 1 percent or less of ketoconazole. The most commonly known OTC brand is Nizoral, which is available in most supermarkets and online for purchase.

You can obtain shampoos that contain 2 percent or more of ketoconazole with a prescription from your doctor. Brands available by prescription include:

  • Ketozal
  • Ketozolin
  • Ket Med

Ketoconazole can have negative side effects that you should be aware of before using it. One of the most common side effects is skin irritation, which can take the form of pimple-like bumps where it’s used. In some individuals, it may also cause either oiliness or dryness of the hair or scalp, abnormal hair texture, or discoloration. It can cause permed hair to lose its curl as well.

In rare cases, ketoconazole shampoo can result in hair loss, so talk to your doctor right away if you notice this side effect.

Signs of allergic reaction

Allergic reactions to ketoconazole shampoo are extremely rare, but should be taken seriously. Seek immediate medical attention if you have signs of an allergic reaction like:

  • severe itching
  • swelling of the face, tongue, or throat
  • difficulty breathing
  • rash
  • dizziness

Other considerations

Ketoconazole’s effects on women who are pregnant or breastfeeding aren’t well-studied. If you’re pregnant and have concerns about using an antifungal treatment, talk to your doctor before using even the OTC version of this antifungal shampoo.

The safety of ketoconazole also hasn’t been well-studied in children. It’s best you don’t use it on anyone under the age of 12 unless instructed by their pediatrician.

You should use a ketoconazole shampoo as instructed by your doctor or as indicated on the product label.

If you’re treating the scalp, apply the shampoo to wet hair. Lather it well, giving it time to soak into the scalp before rinsing. You can then condition the ends of your hair, rinse, and dry as you normally would.

If you’re using ketoconazole shampoo on an area other than the scalp, apply it to the affected area and let it sit for five minutes. Wash it off thoroughly with water, and then dry your skin.

How often and how long you use the shampoo will depend on a number of different factors. These include the strength of the shampoo (either 1 percent for OTC or 2 percent for prescription medication), the condition you’re treating, and the severity of your current symptoms. Your doctor may ask you to use it as often as every other day or as infrequently as once a week depending on these factors.

Use ketoconazole shampoo exactly as directed by your doctor — never more or less frequently. You should begin to see results within two to four weeks after you begin using the shampoo, unless your doctor informs you otherwise for your particular condition. If you don’t see any improvement after a month, call your doctor to ask if a change of course is needed.

If ketoconazole shampoo doesn’t work for your skin condition, you might try other alternatives. This may include other medications, like oral antifungals, to help you treat your overall condition or more widespread infections.

There are also other medicated shampoos that you can try. These include:

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