Methoxsalen is used to treat severe cases of a skin disease called psoriasis. It must be used in combination with special light waves, called ultraviolet (UVA) radiation, but this treatment can sometimes lead to eye damage, skin aging, and skin cancer.
Methoxsalen is a psoralen. It works as a photosensitizer, meaning it absorbs light and makes your skin more sensitive to UVA radiation. When given in combination with UVA radiation waves, methoxsalen damages the DNA in your skin cells, leading to inflammation. Psoriasis is a condition where your skin cells are growing too quickly. By damaging those skin cells, methoxsalen stops those cells from multiplying (growing) and after several days to weeks, your skin cells recover with improved color and thickness.
The following side effects may get better over time as your body gets used to the medication. Let your healthcare provider know immediately if you continue to experience these symptoms or if they worsen over time.
Methoxsalen only:
Combination of methoxsalen and UVA radiation therapy:
Methoxsalen only:
Combination of methoxsalen and UVA radiation therapy:
Contact your healthcare provider immediately if you experience any of the following.
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:
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 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.
It might take anywhere from 6 to 8 weeks for skin lesions to go away. Long-term treatment is typically needed to keep psoriasis symptoms under control. Work with your healthcare provider to discuss your treatment goals.
You should take methoxsalen 1.5 to 2 hours before your scheduled UVA radiation therapy. If you forget to take your dose for any reason, call your healthcare provider right away for guidance on what to do next. Don't undergo UVA radiation therapy if you forget to take methoxsalen because the UVA therapy might not work as well.
Avoid exposing your skin and lips to sunlight for at least 8 hours after using methoxsalen and UVA light treatment. Also, don’t expose your skin to sunlight or sun lamps for 24 hours before or after treatment. Be sure to wear special sunglasses that completely block or absorb UVA light right after you take methoxsalen. Continue wearing these sunglasses for 24 hours if you’re exposed to any light, including sunlight through windows, clouds, or a reflection, and avoid sunbathing for 48 hours.
There's a higher chance of skin aging and skin cancer, including melanoma, with methoxsalen and UVA radiation therapy. If you have a history of skin cancer, discuss with your healthcare provider before starting treatment. Check your skin regularly for any growths or sores that don't heal, and tell your provider if you notice anything worrisome.
It’s not known if methoxsalen and UVA radiation therapy can harm unborn babies or affect your ability to have a baby (fertility), so it’s important to discuss effective birth control methods with your healthcare provider. If you become pregnant, tell your provider right away because you might have to stop taking methoxsalen. If you're of childbearing age, discuss the risks and benefits of methoxsalen with your provider, and take it only if necessary.
Methoxsalen can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.
Because it can cause serious side effects, methoxsalen with UVA radiation should only be used under the care and supervision of an experienced physician who has special training using this treatment. Your physician will discuss risks and serious side effects, such as eye damage, skin aging, and skin cancer, with you before starting treatment.
Methoxsalen is now available in a new dosage form as a softgel capsule. Compared to the old dosage form that was previously on the market, this new capsule form gets absorbed in your body better and works faster as well. It's important to follow the dose prescribed by your healthcare provider, and ask your pharmacist or provider if you have any questions regarding your dose.
Serious skin burns can result if you take higher doses of methoxsalen than prescribed or from having more exposure to UVA light than expected. Methoxsalen with UVA radiation therapy also makes your skin more sensitive to sunlight, even sunlight coming in through windows, so your skin might burn more easily. Follow your prescribed dose and don't make any dose changes without discussing with your healthcare provider first.
Taking methoxsalen raises your risk of developing certain skin cancers, such as melanoma and cutaneous squamous cell cancer, especially at higher doses. Lower doses of methoxsalen and less exposure to UVA radiation can greatly reduce your risk, but skin cancer can still occur even after you've stopped treatment. If you notice any unusual skin changes, such as a new growth or new mole that's odd in size, shape, or color, tell your healthcare provider right away.
Exposing your eyes to UVA radiation waves after taking methoxsalen can damage the lens of your eyes and cause cataracts. To prevent cataracts, it's important to protect your eyes by wearing special UVA-absorbing, wrap-around sunglasses during UVA therapy and for 24 hours after having UVA treatment. Visit your eye doctor for routine eye exams before starting treatment and yearly.
Exposure to sunlight and long-term treatment with methoxsalen and UVA radiation can cause aging of your skin. Wear a hat or gloves and apply a sunscreen with SPF 15 or greater with ingredients that protect against UVA radiation, such as benzophenone and PABA esters, to help protect your skin and lips from sunlight. Don't use sunscreen on areas of your skin affected by psoriasis until after your scheduled UVA treatment.
Take methoxsalen with caution if you have a history of basal cell cancer, which is a type of skin cancer. If you notice any changes in your skin, such as open sores that won't go away or itchy red patches on your face, chest, arms, or legs, let your healthcare provider know right away.
Take methoxsalen with caution if you're older or have liver problems, because your liver helps break down methoxsalen so it can be cleared from your body through your urine. If you have liver problems, let your healthcare provider know, because the medication can buildup in your body and cause serious side effects.
Take methoxsalen with caution, especially if you're older and have heart problems, such as blood pressure problems, because exposure to UVA radiation can cause your blood pressure to drop. If you have trouble standing for long periods of time or you can't tolerate heat, let your healthcare provider know because you might need to be treated with a different type of UVA chamber.
| Dosage | Quantity | Price as low as | Price per unit |
|---|---|---|---|
| 10mg | 12 capsules | $224.31 | $18.69 |
The dose of methoxsalen is based on your body weight and the number of doses you’ll take per week depends on your schedule of UVA radiation therapy, but all doses must be separated by at least 2 days. Older adults will typically be started on lower doses. Take your dose 1.5 to 2 hours before your scheduled UVA radiation therapy.
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 taking this medicine, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.
Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Contraindications are specific health conditions or situations in which a person should not take a medication due to safety concerns. If you have any of the following conditions or if any of the following apply to you, let your healthcare provider know because Methoxsalen will not be safe for you to take.