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Selenos (Topical)

Generic name: selenium sulfide

Brand names: Dandrex, Selenos, SelRx, Selseb, Selsun Blue Medicated Treatment, Tersi Foam

Last updated August 22, 2026 0 views
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Uses for Selenos

Selenium sulfide 1% and 2.5% strengths are used on the scalp to help manage dandruff and seborrheic dermatitis.

Selenium sulfide 2.5% strength is also used on the body to treat tinea versicolor (a type of skin fungus infection).

In the United States, you can only get the 2.5% strength with a doctor's prescription.

This section was rewritten for readability and reviewed for meaning.

Precautions while using Selenos

If your condition does not improve after using this medicine regularly, or if it worsens, contact your doctor.

This section was rewritten for readability and reviewed for meaning.

Before using Selenos

In deciding to use a medicine, you need to consider the risks and benefits. This is a choice you and your doctor will make together. For this medicine, keep the following in mind:

Allergies

Inform your doctor if you have ever had any unusual or allergic reactions to this medicine or any other medicines. Also, let your healthcare professional know if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, carefully read the label or package ingredients.

Pediatric

There is no specific information comparing the use of selenium sulfide in infants and children to other age groups; however, this medicine is not expected to cause different side effects or problems in children than it does in adults.

Geriatric

Many medicines have not been specifically studied in older people. Therefore, it may not be known if they work the same way in older adults as they do in younger adults. Although there is no specific information comparing the use of selenium sulfide in the elderly with use in other age groups, this medicine is not expected to cause different side effects or problems in older people than it does in younger adults.

Interactions with Medicines

Some medicines should not be used together at all, while others may be used together despite potential interactions. In these cases, your doctor may want to adjust the dose, or other precautions may be needed. Inform your healthcare professional if you are taking any other prescription or nonprescription (over-the-counter [OTC]) medicine.

Interactions with Food/Tobacco/Alcohol

Certain medicines should not be used around the time of eating food or certain kinds of food due to possible interactions. Using alcohol or tobacco with certain medicines may also lead to interactions. Discuss with your healthcare professional how to use your medicine with food, alcohol, or tobacco.

Other Medical Problems

Having other medical problems may affect the use of this medicine. Be sure to tell your doctor if you have any other medical issues, especially:

  • Blistered, raw, or oozing areas on your scalp or body—Using this medicine on these areas may increase the chance of absorption through the skin.

This section was rewritten for readability and reviewed for meaning.

Side Effects of Selenos

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

Less common or rare

  • Skin irritation

Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common

  • Unusual dryness or oiliness of hair or scalp

Less common

  • Increase in normal hair loss

Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.

Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

In the U.S.

  • Dandrex
  • Selenos
  • SelRx
  • Selseb
  • Selsun Blue Medicated Treatment
  • Tersi Foam

In Canada

  • Versel

Available Dosage Forms:

  • Shampoo
  • Lotion
  • Foam

Therapeutic Class: Antiseborrheic

This section was rewritten for readability and reviewed for meaning.

Proper use of Selenos

If you are using the 2.5% strength of selenium sulfide: Use this medicine only as directed. Do not use it more often than recommended on the label, unless otherwise directed by your doctor.

If you are using the 1% strength of selenium sulfide: For best results, use this medicine at least 2 times a week or as directed by your doctor.

To use selenium sulfide for dandruff or seborrheic dermatitis of the scalp:

  • Before using this medicine, wet the hair and scalp with lukewarm water.
  • Apply enough medicine (1 or 2 teaspoonfuls) to the scalp to work up a lather. Allow the lather to remain on the scalp for 2 to 3 minutes, then rinse.
  • Apply the medicine again and rinse well.
  • If this medicine is used on light or blond, gray, or chemically treated (bleached, tinted, permanent-waved) hair, rinse your hair well for at least 5 minutes after using the medicine to lessen the chance of hair discoloration.
  • After treatment, wash your hands well.

To use selenium sulfide for tinea versicolor of the body:

  • Apply the medicine to the affected areas of your body, except for your face and genitals (sex organs).
  • Work up a lather using a small amount of water.
  • Allow the medicine to remain on your skin for 10 minutes.
  • Rinse your body well to remove all the medicine.

Do not use this medicine if blistered, raw, or oozing areas are present on your scalp or the area of your body that is to be treated, unless otherwise directed by your doctor.

Keep this medicine away from the eyes. If you should accidentally get some in your eyes, flush them thoroughly with water.

Dosing

The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

  • For lotion dosage form: For dandruff or seborrheic dermatitis: Adults and children—If you are using the 1% lotion, use on the scalp two times a week. If you are using the 2.5% lotion, use on the scalp two times a week for two weeks, then use one time a week or less often. Infants—Use and dose must be determined by your doctor. For tinea versicolor: Adults and children—Use the 2.5% lotion on the body one time a day for seven days. Infants—Use and dose must be determined by your doctor.

Missed Dose

If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

Storage

Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.

Keep out of the reach of children.

Do not keep outdated medicine or medicine no longer needed.

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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.