In the U.S.—

In Canada—

• Antipsoriatic, topical
• Hair growth stimulant, alopecia areata, topical
• Repigmenting agent, topical

Methoxsalen ( meth-OX-a-len) belongs to the group of medicines called psoralens. It is used along with ultraviolet light (found in sunlight and some special lamps) in a treatment called psoralen plus ultraviolet light A (PUVA) to treat vitiligo, a disease in which skin color is lost. Methoxsalen may also be used for other conditions as determined by your doctor.

Methoxsalen is available only with a prescription and is to be administered by or under the direct supervision of your doctor, in the following dosage form:

Topical
• Topical solution (U.S. and Canada)

Methoxsalen is a very strong medicine that increases the skin's sensitivity to sunlight. In addition to causing serious sunburns if not properly used, it has been reported to increase the chance of skin cancer. Also, like too much sunlight, PUVA can cause premature aging of the skin. Therefore, methoxsalen should be used only as directed and should not be used simply for suntanning. Before using this medicine, be sure that you have discussed its use with your doctor.

In deciding to use a medicine, the risks of using the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For topical methoxsalen, the following should be considered:

Allergies—Tell your doctor if you have ever had any unusual or allergic reaction to methoxsalen. Also tell your health care professional if you are allergic to any other substances, such as foods, preservatives, or dyes.

Diet—Eating certain foods while you are using methoxsalen may increase your skin's sensitivity to sunlight. To help prevent this, avoid eating limes, figs, parsley, parsnips, mustard, carrots, and celery while you are being treated with this medicine.

Pregnancy—Studies on effects in pregnancy have not been done in either humans or animals.

Breast-feeding—It is not known whether methoxsalen passes into breast milk. Although most medicines pass into breast milk in small amounts, many of them may be used safely while breast-feeding. Mothers who are taking this medicine and who wish to breast-feed should discuss this with their doctor.

Children—Studies on this medicine have been done only in adult patients, and there is no specific information comparing use of methoxsalen in children up to 12 years of age with use in other age groups.

Older adults—Many medicines have not been studied specifically in older people. Therefore, it may not be known whether they work exactly the same way they do in younger adults or if they cause different side effects or problems in older people. There is no specific information comparing use of topical methoxsalen in the elderly with use in other age groups.

Other medicines—Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are using topical methoxsalen, it is especially important that your health care professional know if you are receiving the following:

• Recent treatment with x-rays or cancer medicines or plans to have x-rays in the near future—Increases the chance of side effects from treatment with PUVA

• Allergy to sunlight (or family history of) or
• Infection or
• Lupus erythematosus or
• Porphyria or
• Skin cancer (history of) or
• Skin conditions (other)—Use of PUVA may make the condition worse

• Heart or blood vessel disease (severe)—The heat or prolonged standing associated with each light treatment may make the condition worse

Use this medicine only under the direct supervision of your doctor.

After UVA exposure, wash the treated area of skin with soap and water. Then use a sunscreen or wear protective clothing to protect the area.

Dosing—

Follow your doctor's directions in using this medicine. The following information includes only the average doses of methoxsalen. If your dose is different, do not change it unless your doctor tells you to do so.

• For topical solution dosage form:
  • For vitiligo:
    • Adults and children 12 years of age and over—Apply to the affected area of the skin and allow to dry for one to two minutes, then apply again within two to two and one-half hours before UVA exposure.
    • Children under 12 years of age—Use and dose must be determined by your doctor.

It is important that you visit your doctor as directed for treatments and to have your progress checked.

This medicine increases the sensitivity of the treated areas of your skin to sunlight. Therefore, exposure to the sun, even through window glass or on a cloudy day, could cause a serious burn. After each light treatment, thoroughly wash the treated areas of your skin. Also, if you must go out during daylight hours, cover the treated areas of your skin for at least 12 to 48 hours following treatment by wearing protective clothing or a sun block product that has a skin protection factor (SPF) of at least 15. Some patients may require a product with a higher SPF number, especially if they have a fair complexion. If you have any questions about this, check with your health care professional.

The treated areas of your skin may continue to be sensitive to sunlight for some time after treatment with this medicine. Use extra caution for at least 72 hours following each treatment if you plan to spend any time in the sun. In addition, do not sunbathe anytime during your course of treatment with methoxsalen.

This medicine may cause your skin to become dry or itchy. However, check with your doctor before applying anything to your skin to treat this problem.

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 immediately if any of the following side effects occur, since they may indicate a serious burn:

• Blistering and peeling of skin;  reddened, sore skin;  swelling, especially of the feet or lower legs 

There is an increased risk of developing skin cancer after use of methoxsalen. You should check the treated areas of your body regularly and show your doctor any skin sores that do not heal, new skin growths, and skin growths that have changed in the way they look or feel.

Premature aging of the skin may occur as a result of prolonged methoxsalen therapy. This effect is permanent and is similar to the result of sunbathing for long periods of time.

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

Once a medicine has been approved for marketing for a certain use, experience may show that it is also useful for other medical problems. Although these uses are not included in product labeling, topical methoxsalen is used in certain patients with the following medical conditions:

• Alopecia areata
• Eczema
• Inflammatory dermatoses
• Lichen planus
• Mycosis fungoides
• Need to increase tolerance of skin to sunlight
• Psoriasis

Other than the above information, there is no additional information relating to proper use, precautions, or side effects for these uses.