Methoxsalen works by enhancing the body's sensitivity to ultraviolet light A (UVA).

Methoxsalen injection is used with UVA light therapy to treat skin lesions caused by cutaneous T-cell lymphoma (CTCL). Methoxsalen treats only the skin symptoms of CTCL but does not treat lymphoma.

Methoxsalen may also be used for purposes not listed in this medication guide.

You should not be treated with methoxsalen if you are sensitive to light or if you have lens damage in your eye.

Methoxsalen injection is given as part of a procedure called photopheresis (FOE-toe-fe-REE-sis).

During photopheresis, some of your blood is collected through a small tube (catheter) placed into a vein. The catheter is connected to a machine that separates your white blood cells from other parts of the blood.

The white blood cells are then mixed with methoxsalen and exposed to UVA light. When injected back into your body, these treated blood cells help strengthen your immune system to lessen the skin lesions of CTCL.

This treatment is usually given for 2 days in a row every 4 weeks for at least 6 months.

Methoxsalen will make you more sensitive to sunlight, which can cause harmful effects on your vision and on your skin (premature aging or skin cancer).

For at least 24 hours after each photopheresis treatment:

• You must protect your skin and eyes from natural sunlight (even sun shining through a window).

• Do not expose your skin to any sunlight. Wear protective clothing including a hat and gloves. Use a sunscreen with a minimum SPF of 15, and apply it to all uncovered skin areas exposed to light.

• Wear a pair of wraparound UVA-absorbing sunglasses for at least 24 hours after treatment, even while you are indoors near a window.

You may develop cataracts if you do not properly protect your eyes after each photopheresis treatment.

Check your skin regularly for signs of skin cancer, such as a small growth or nodule, a scaly or crusted lesion, a brownish spot or speckles, or a change in the size, color, or feel of a mole. You may need to check your skin for signs of cancer throughout the rest of your life.

You should not be treated with methoxsalen if you are allergic to methoxsalen or similar medicines, or if you have:

• lupus, porphyria, albinism, or other conditions that make you more sensitive to light; or

• damage to the lenses of your eyes caused by surgery, injury, or genetic condition.

Tell your doctor if you have ever had:

• a severe sunburn;

• a skin pigment disorder;

• basal cell carcinoma;

• radiation or x-ray therapy, or treatment with arsenic trioxide (Trisenox);

• liver or kidney disease;

• cataracts; or

• heart disease.

Methoxsalen injection may harm an unborn baby. Use effective birth control to prevent pregnancy and tell your doctor if you become pregnant.

It may not be safe to breastfeed while using this medicine. Ask your doctor about any risk.

Call your doctor for instructions if you miss an appointment for your photopheresis treatment.

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222. You will be extremely sensitive to light after an overdose.

Avoid all exposure to sunlight or artificial UV rays between treatments.

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

Methoxsalen may cause serious side effects. Call your doctor at once if you have:

• severe skin redness within 24 hours after UVA treatment;

• swelling, severe itching, or severe skin discomfort;

• an open sore or new skin lesion that is red, scaly, raised, rough, or hardened;

• a light-headed feeling, like you might pass out; or

• blurred vision, tunnel vision, eye pain or swelling, or seeing halos around lights.

Skin redness or thickening may occur several hours or days after photopheresis with methoxsalen injection. This is a normal effect of methoxsalen and UVA treatment, and may not be a sign of severe sunburn. Ask your doctor if you have concerns about any redness or swelling of your skin.

Common side effects of methoxsalen may include:

• rash;

• fever;

• nausea; or

• changes in your sense of taste.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Tell your doctor about all your other medicines. Methoxsalen can make your skin even more sensitive to sunlight if you also use certain other medicines, especially:

• anthralin;

• an antibiotic or a sulfa drug;

• a bacteriostatic soap;

• a diuretic or "water pill";

• coal tar applied to the skin or scalp--such as Neutrogena T/Gel, Psoriasin, Tegrin Medicated;

• medicine to treat mental illness--fluphenazine, prochlorperazine, thioridazine, and others; or

• a staining dye--such as methylene blue, toluidine blue, rose bengal, or methyl orange.

This list is not complete. Other drugs may affect methoxsalen, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.