Trioxsalen (By mouth)


Trioxsalen (trye-OX-sa-len)

Treats loss of skin color that may be caused by skin diseases such as vitiligo. May also increase tolerance to sunlight for patients who are allergic or sensitive to the sun. This medicine was withdrawn from the U.S. market in December 2002.

Brand Name(s)

When This Medicine Should Not Be Used

How to Use This Medicine


  • Your doctor will tell you how much medicine to use and how often.
  • For the medicine to work, you will need to use it 2 to 4 hours before you expose your skin to ultraviolet (UV) light. UV light is in sunlight and may be in the lights in tanning beds or sun lamps. Your doctor will tell you how long you should be in UV light.
  • Using more of the medicine or spending longer periods in the sun or other UV light than your doctor ordered can cause bad burns or blisters on your skin.
  • You may take the medicine with milk or after meals to decrease stomach upset.
  • Never share your medicine with anyone.

If a dose is missed:

  • Use the missed dose as soon as possible. Then wait 2 to 4 hours (or as your doctor ordered) before you expose your skin to sunlight or other UV light.
  • You should not use two doses at the same time.

How to Store and Dispose of This Medicine

  • Store the tablets at room temperature, away from heat, moisture, and direct light.
  • Keep all medicine out of the reach of children.

Drugs and Foods to Avoid

Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.

  • Avoid eating limes, figs, parsley, parsnips, mustard, carrots, and celery while on trioxsalen therapy. Eating these foods while using trioxsalen may cause bad burns or blisters.
  • You should not use trioxsalen with other medicine that makes your skin sensitive to sunlight, such as sulfa drugs and tretinoin (Renova®, Retin-A®). There are many other drugs that can cause your skin to be sensitive to sunlight. Make sure you tell your doctor all the medicines you use, including those you get without a prescription.

Warnings While Using This Medicine

  • You must wear sunscreen on your lips and special sunglasses that block UV light when you have your treatments.
  • Your skin will be sensitive to sunlight for about 8 to 12 hours after each treatment. Wear a hat and protect your skin with clothing and sunscreen when you are outside. You may need to wear the special sunglasses for about 12 hours after your treatment to protect your eyes. Talk with your doctor about this.
  • You should not use trioxsalen for more than 14 days if you are using the medicine for tanning or to increase tolerance to sunlight.
  • If you are pregnant or breastfeeding, talk with your doctor before using this medicine.

Possible Side Effects While Using This Medicine

Call your doctor right away if you notice any of these side effects:

  • Blistering or red, painful skin.

If you notice these less serious side effects, talk with your doctor:

  • Upset stomach.

If you notice other side effects that you think are caused by this medicine, tell your doctor

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

Version Info

  • Last reviewed on 12/4/2015

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