Methoxsalen
Antipsoriasis · Photosensitizer
Indications
Psoriasis, idiopathic vitiligo (in conjunction with UV radiation or photosensitizing agent).
Dosage
ORAL: Take with milk or after food as a single dose, or in 2 divided doses, approx 30 min apart to minimize GI side effects. Idiopathic vitiligo: Adults & Children: Above 12 yr: 20 mg/day 2-4 hr before exposure to UVA or sunlight. Therapy should be on alternate days & never on 2 consecutive days. Max dose: 0.6 mg/kg. Psoriasis: Adults: 10-70 mg, 1.5-2 hr before exposure to UVA, administered 2-3 times wkly. TOPICAL: Vitiliginous lesions: Adults: The soln/cream after dilution to 0.1% or 0.01% applied once wkly for 6-9 mth. Surrounding skin should be protected by an opaque screen, the treated area should be exposed to UVA after waiting up to 2 hr. After exposure the lesions should be washed and protected from light for up to 48 hr or longer. Psoriasis: Adults: The preparation is diluted 0.15% (or to 0.015%). Applied to the affected area 15 min before UVA exposure. Alternatively whole body…
Adverse Effects
Oedema, hypotension, nervousness, vertigo, depression, painful blistering, burning, pruritus, hypo-pigmentation, rash, cheilitis, erythema, itching, nausea, loss of muscle coordination.
Risk Factor (Pregnancy/Lactation)
Contraindications: Diseases associated with light sensitivity (lupus erythematosus, porphyria). Hypertension, heart, liver or kidney failure. Precautions: Protect eyes & skin against complementary sun exposure after controlled UV irradiation. Monitor patients on possible long-term risks of photo-chemotherapy e.g. skin aging, changes in pigmentation, risk of basal cell epithelioma & cataract.
Interactions
Photosensitizing agents e.g. anthracin, coal tar, griseofulvin, phenothiazine, nalidixic acid, halogenated salicylamide, sulphonamides, tetracycline, thiazides, organic dyes.
Brands with this active ingredient
Compiled by Healify Pharmacy from published drug references. How we compile it →
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