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Dandrex

Generic name: selenium sulfide topical

Brand names: Dandrex, Selsun Blue 2 in 1, Selsun Blue Balanced Treatment, Selsun Blue Medicated Treatment, Selsun Blue Moisturizing Treatment, SelRx, Tersi Foam

Last updated November 2, 2026 0 views
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What is Dandrex?

Selenium sulfide is a medication that fights fungus. It stops fungus from growing on your skin.

Dandrex (for the skin) is used to treat dandruff, seborrhea, and tinea versicolor (a fungus that causes skin discoloration).

Dandrex may also be used for other reasons not mentioned in this medication guide.

This section was rewritten for readability and reviewed for meaning.

Warnings

Follow all instructions on your medicine label and package. Inform each of your healthcare providers about all your medical conditions, allergies, and all medicines you are using.

This section was rewritten for readability and reviewed for meaning.

Before taking this medicine

You should not use Dandrex if you are allergic to selenium sulfide.

FDA pregnancy category C. It is not known whether Dandrex will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant while using this medication.

It is not known whether selenium sulfide topical passes into breast milk or if it could harm a nursing baby. Tell your doctor if you are breast-feeding a baby.

Dandrex should not be used on a child younger than 2 years old without a doctor's advice.

This section was rewritten for readability and reviewed for meaning.

Dandrex side effects

Get emergency medical help if you notice any of these signs of an allergic reaction: hives; trouble breathing; swelling of your face, lips, tongue, or throat.

Stop using selenium sulfide and contact your doctor if you experience unusual or severe blistering, itching, redness, peeling, dryness, or irritation of the skin that was treated.

This is not a complete list of side effects, and others may happen. Reach out to your doctor for medical advice about side effects. You can report side effects to the FDA at 1-800-FDA-1088.

This section was rewritten for readability and reviewed for meaning.

How should I use Dandrex?

Use this medicine exactly as directed on the label, or as prescribed by your doctor. Do not use it in larger amounts or for longer than recommended.

Shake the selenium sulfide foam, lotion, or shampoo well just before each use.

Wash your hands after applying the foam or lotion.

Rinse the shampoo thoroughly. Do not leave it in your hair for an extended period of time. Dandrex shampoo is generally not for daily use. Follow the directions on the label, or your doctor's instructions.

Use this medication for the full prescribed length of time. Your symptoms may improve before the infection is completely cleared.

Call your doctor if your symptoms do not improve, or if they get worse while using Dandrex.

Do not cover treated skin with a bandage or other dressing unless your doctor has told you to. A light cotton-gauze bandage may be used to protect clothing.

Store at room temperature away from moisture and heat. Keep the foam canister away from open flame, and do not puncture the can.

What happens if I miss a dose?

Apply the missed dose as soon as you remember. If it is nearly time for your next dose, wait until then to use the medicine and skip the missed dose. Do not apply extra medicine to make up for the missed dose.

This section was rewritten for readability and reviewed for meaning.

What happens if I overdose?

An overdose of Dandrex is not expected to be dangerous. Seek emergency medical help or call the Poison Help line at 1-800-222-1222 if someone accidentally swallows the medication.

Avoid getting Dandrex in your eyes, nose, mouth, rectum, or vagina. If it gets into any of these areas, rinse with water. Do not use Dandrex on sunburned, windburned, dry, chapped, or broken skin.

Avoid covering treated skin areas with tight-fitting, synthetic clothing that does not allow air circulation. Wear loose-fitting clothing made of cotton and other natural fibers until your infection is healed.

This section was rewritten for readability and reviewed for meaning.

What other drugs will affect Dandrex?

Avoid using other topical medications while you are applying Dandrex, unless your doctor says it's okay. Other skin medications may change how well selenium sulfide topical works or how your skin absorbs it.

This section was rewritten for readability and reviewed for meaning.

Related medicines

Before you take this medicine: the information on this page is general and may not cover your personal circumstances. Read the label supplied with your medicine and ask a pharmacist or doctor if you are unsure, especially if you are pregnant, breastfeeding, taking other medicines or managing a long-term condition.
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Content is provided for education and is not medical advice. See our medical disclaimer.