METHOXSALEN (Systemic)

Some commonly used brand names are:

In the U.S.?

• 8-MOP
• Oxsoralen-Ultra

In Canada?

• Oxsoralen
• Ultra MOP
• Oxsoralen-Ultra

Category

• Antineoplastic
• Antipsoriatic,systemic
• Hair growth stimulant, alopecia areata,systemic
• Repigmenting agent, systemic

Description

Methoxsalen (meth-OX-a-len) belongsto the group of medicines called psoralens. It is used along with ultravioletlight (found in sunlight and some special lamps) in a treatment called PUVAto treat vitiligo, a disease in which skin color is lost, and psoriasis, askin condition associated with red and scaly patches.

Methoxsalen is also used with ultraviolet light in the treatment of whiteblood cells. This treatment is called photopheresis and is used to treat theskin problems associated with mycosis fungoides, which is a type of lymphoma.

Methoxsalen may also be used for other conditions as determined by yourdoctor.

This medicine is available only with your doctor's prescription, in thefollowing dosage forms:

Oral
• Hard gelatin capsules (U.S. and Canada)
• Soft gelatin capsules (U.S. and Canada)

Before Using This Medicine

Methoxsalen is a very strongmedicine that increases the skin's sensitivity to sunlight. In addition tocausing serious sunburns if not properly used, it has been reported to increasethe chance of skin cancer and cataracts. Also, like too much sunlight, PUVAcan cause premature aging of the skin. Therefore, methoxsalen should be usedonly as directed and it should not be used simplyfor suntanning. Before using this medicine, be sure that you have discussedits use with your doctor.

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

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

Pregnancy?Studies on effects in pregnancy havenot been done in either humans or animals.

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

Children?Some of the side effects are more likely to occurin children up to 12 years of age, since these children may be more sensitiveto the effects of methoxsalen.

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

Other medicines?Although certain medicines should not be usedtogether at all, in other cases two different medicines may be used togethereven if an interaction might occur. In these cases, your doctor may want tochange the dose, or other precautions may be necessary. When you are usingmethoxsalen, it is especially important that your health care professionalknow if you are using the following:

• Arsenicals or recent treatment with x-rays, or cancer medicines orplans to have x-rays in the near future?Arsenicals, x-rays and cancermedicines increase the chance of side effects from treatment with PUVA

Other medical problems?The presence of other medicalproblems may affect the use of methoxsalen. Make sure you tell your doctorif you have any other medical problems, especially:

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

• Eye problems, such as cataracts or loss of the lens of the eye?Thelight treatment may make the condition worse or may cause damage to the eye

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

• Liver disease?Condition may cause increased blood levels ofthe medicine and cause an increase in side effects

Proper Use of This Medicine

Eating certainfoods while you are taking methoxsalen may increase your skin's sensitivityto sunlight. To help prevent this, avoid eating limes, figs, parsley, parsnips,mustard, carrots, and celery while you are being treated with this medicine.

Methoxsalen usually comes with patient directions. Read them carefullybefore using this medicine.

This medicine may take 6 to 8 weeks to really help your condition. Do not increase the amount of methoxsalen you are taking orspend extra time in the sunlight or under an ultraviolet lamp. Thiswill not make the medicine act any more quickly and may result in a seriousburn.

If this medicine upsets your stomach:

• Patients taking the hard gelatin capsules may take them with foodor milk.
• Patients taking the soft gelatin capsules may take them with low-fatfood or low-fat milk.

Dosing?The dose of methoxsalen will be different fordifferent patients. Follow your doctor's orders or thedirections on the label. The following information includes only theaverage doses of methoxsalen. If your dose is different,do not change it unless your doctor tells you to do so.

The number of capsules that you take depends on the strength of the medicine.Also, the number of doses you take each day, the timeallowed between doses, and the length of time you take the medicine dependon the medical problem for which you are taking methoxsalen.

• For oral dosage form (hard gelatin capsule):
  • For treating mycosis fungoides and psoriasis:
    • Adults and children 12 years of age and over?Dose is basedon body weight and must be determined by your doctor. However, the usual doseis 0.6 mg per kilogram (kg) (0.27 mg per pound) of body weight taken two hoursbefore UVA exposure. This treatment (methoxsalen and UVA) is given two orthree times a week with the treatment spaced at least forty-eight hours apart.
    • Children up to 12 years of age?Dose must be determined by yourdoctor.
  • For vitiligo:
    • Adults and children 12 years of age and over?20 milligrams(mg) per day taken two to four hours before ultraviolet light A (UVA) exposure.This treatment (methoxsalen and UVA) is given two or three times a week withthe treatment spaced at least forty-eight hours apart.
    • Children up to 12 years of age?Dose must be determined by yourdoctor.
• For oral dosage form (soft gelatin capsule):
  • For psoriasis:
    • Adults and children 12 years of age and over?Dose is basedon body weight and must be determined by your doctor. The usual dose is 0.4mg per kg (0.18 mg per pound) of body weight taken one and one-half to twohours before UVA exposure. This treatment (methoxsalen and UVA) is given twoor three times a week, with the treatment spaced at least forty-eight hoursapart.
    • Children up to 12 years of age?Dose must be determined by yourdoctor.

Missed dose?If you are late in taking, or miss taking, a doseof this medicine, notify your doctor so your light treatment can be rescheduled.Remember that exposure to sunlight or ultraviolet light must take place acertain number of hours after you take the medicineor it will not work. For patients taking the hard gelatin capsules, this is2 to 4 hours. For patients taking the soft gelatin capsules, this is 11/2to 2 hours. If you have any questions about this, check with your doctor.

Storage?To store this medicine:

• Keep out of the reach of children.
• Store away from heat and direct light.
• Do not store in the bathroom, near the kitchen sink, or in otherdamp places. Heat or moisture may cause the medicine to break down.
• Do not keep outdated medicine or medicine no longer needed. Be surethat any discarded medicine is out of the reach of children.

Precautions While Using This Medicine

Yourdoctor should check your progress at regular visits to make sure this medicineis working and that it does not cause unwanted effects. Eye examinations shouldbe included.

This medicine increases the sensitivity of your skin and lips to sunlight.Therefore, exposure to the sun, even through window glassor on a cloudy day, could cause a serious burn. If you must go outduring the daylight hours:

• Before each treatment, cover your skin for atleast 24 hours by wearing protective clothing, such as long-sleevedshirts, full-length slacks, wide-brimmed hat, and gloves. In addition, protect your lips with a special sun block lipstick that hasa skin protection factor (SPF) of at least 15. Check with your doctorbefore using sun block products on other parts of your body before a treatment,since sun block products should not be used on the areas of your skin thatare to be treated.
• After each treatment, cover your skin for atleast 8 hours by wearing protective clothing. In addition, use a sunblock product that has a skin protection factor (SPF) of at least 15 on yourlips and on those areas of your body that cannot be covered.

If you have any questions about this, check with your health care professional.

Your skin may continue to be sensitive to sunlight for some time aftertreatment with this medicine. Use extra caution for at least 48 hours followingeach treatment if you plan to spend any time in the sun. In addition, do notsunbathe anytime during your course of treatment with methoxsalen.

For 24 hours after you take each dose of methoxsalen,your eyes should be protected during daylight hours with special wraparoundsunglasses that totally block or absorb ultraviolet light (ordinarysunglasses are not adequate). This is to prevent cataracts. Your doctor willtell you what kind of sunglasses to use. These glasses should be worn evenin indirect light, such as light coming through window glass or on a cloudyday.

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

Side Effects of This Medicine

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 mayneed medical attention.

Check with your doctor immediately if you thinkyou have taken an overdose or 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 feet or lowerlegs)

Otherside effects may occur that usually do not need medical attention. These sideeffects may go away during treatment as your body adjusts to the medicine.However, check with your doctor if any of the following side effects continuefor more than 48 hours or are bothersome:

More common

Itching of skin; nausea

Less common

Dizziness; headache; mental depression; nervousness; trouble in sleeping

Treatment with thismedicine usually causes a slight reddening of your skin 24 to 48 hours afterthe treatment. This is an expected effect and is no cause for concern. However,check with your doctor right away if your skin becomes sore and red or blistered.

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

Premature aging of the skin may occur as a result of prolonged methoxsalentherapy. This effect is permanent and is similar to what happens when a personsunbathes for long periods of time.

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

Additional Information

Once a medicine has been approvedfor marketing for a certain use, experience may show that it is also usefulfor other medical problems. Although these uses are not included in the productlabeling, methoxsalen is used in certain patients with the following medicalconditions:

• Alopecia areata
• Atopic dermatitis
• Eczema
• Lichen planus
• Skin that is abnormally sensitive to sunlight