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- What is methoxsalen-topical, and how does it work (mechanism of action)?
- What brand names are available for methoxsalen-topical?
- Is methoxsalen-topical available as a generic drug?
- Do I need a prescription for methoxsalen-topical?
- What are the uses for methoxsalen-topical?
- What are the side effects of methoxsalen-topical?
- What is the dosage for methoxsalen-topical?
- Which drugs or supplements interact with methoxsalen-topical?
- Is methoxsalen-topical safe to take if I'm pregnant or breastfeeding?
- What else should I know about methoxsalen-topical?
What is methoxsalen-topical, and how does it work (mechanism of action)?
- Methoxsalen is a naturally occurring photoactive chemical found in the seeds of the Ammi majus (Umbelliferae) plant and in the roots of Heraclem candicans. It belongs to a group of compounds known as psoralens, or furocoumarins. Methoxsalen lotion is used for treating vitiligo (leucoderma). The exact mechanism of action of methoxsalen is not known.
- Methoxsalen has several biological actions that may be responsible for its medical effects. Methoxsalen is a photosensitizer that increases the reaction of skin cells to UVA. Some experts suggest that methoxsalen improves vitiligo by stimulating melanocytes (melanin forming skin cells) to move up the hair follicle and to repopulate the epidermis. Methoxsalen also combines with DNA in skin cells, leading to inhibition of DNA synthesis, cell division, and reduced formation of new skin cells. Administration of methoxsalen combined with UVA exposure causes cellular damage, leading to skin inflammation and erythema. The damaged skin heals after several days to weeks.
- The FDA approved methoxsalen lotion in December 1954.
What are the uses for methoxsalen-topical?
- Methoxsalen lotion is a topical repigmenting agent for treating vitiligo (leucoderma). It is used in conjunction with controlled doses of ultraviolet A light (UVA, 320-400 nm) or sunlight.
What is the dosage for methoxsalen-topical?
- Methoxsalen lotion should be applied to the affected area 2 hr. before UV exposure every 3 to 7 days.
- It takes a few weeks for pigmentation to begin.
- Significant repigmentation may take 6 to 9 months of treatment and re-treatment may be necessary to retain the new pigment.
Which drugs or supplements interact with methoxsalen-topical?
Is methoxsalen-topical safe to take if I'm pregnant or breastfeeding?
- Methoxsalen lotion has not been studied in pregnant women and it is not known whether methoxsalen can harm the fetus when used by a pregnant woman. It is not known whether methoxsalen is absorbed into the blood stream when it is applied to the skin. Methoxsalen lotion should be used in pregnant women only when clearly needed.
- It is not known whether methoxsalen is excreted in human milk after it is applied to the skin.
Multimedia: Slideshows, Images & Quizzes
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