Therapeutic Agent for Vulgaris Vitiligo (Methoxsalen) is a photosensitive drug primarily used for treating skin diseases such as vulgaris vitiligo.

How to Use Therapeutic Agent for Vulgaris Vitiligo (Methoxsalen)

Specific Administration Requirements

Swallow whole: The capsules must be swallowed entirely; they should not be split, crushed, chewed, or dissolved.

UVA irradiation dosage: The initial UVA irradiation dosage should be determined based on the patient’s skin type (0.5 J/cm² for Type I skin, 3.0 J/cm² for Type VI skin).

Treatment frequency: 2–3 times per week, with an interval of at least 48 hours between each session.

Course monitoring: During the treatment period, skin reactions and therapeutic effects should be evaluated regularly.

Dosage Adjustment of Therapeutic Agent for Vulgaris Vitiligo (Methoxsalen)

Dosage Adjustment Based on Therapeutic Response

Non-responsive patients: If there is no response after 10 treatment sessions, the UVA dosage may be increased by 0.5–1.0 J/cm².

No response after 15 sessions: A single adjustment of increasing the dosage of Therapeutic Agent for Vulgaris Vitiligo by 10 mg may be considered.

Excessive response: If erythema of Grade 2 or above occurs, treatment should be suspended until the symptoms subside.

Dosage Adjustment Based on Weight Change

When a patient’s weight changes and moves into an adjacent dosage group, it is usually not necessary to adjust the drug dosage. However, the UVA irradiation duration should be adjusted according to skin reactions.

Maintenance Treatment Dosage

Initial maintenance: Once per week.

Gradual reduction: Once every 2 weeks → once every 3 weeks → on-demand treatment.

Maximum UVA dosage: ≤ 12 J/cm² for Type I skin, ≤ 22 J/cm² for Type IV skin.

Administration of Therapeutic Agent for Vulgaris Vitiligo (Methoxsalen) in Special Populations

Patients with Renal Impairment

Mild renal impairment (CrCl 51–80 mL/min): The benefits and risks need to be carefully assessed.

Moderate to severe renal impairment (CrCl ≤ 50 mL/min): Contraindicated, as drug clearance is significantly reduced.

Patients with Hepatic Impairment

Therapeutic Agent for Vulgaris Vitiligo is mainly metabolized by the liver. Patients with hepatic impairment should use it with caution, and adverse drug reactions must be closely monitored.

Elderly Patients

Elderly patients should start with a low dosage and have their therapeutic response closely monitored. Special attention should be paid to potential comorbid eye diseases (e.g., cataracts), cardiovascular diseases, and the risk of skin cancer in elderly patients.

Pregnant and Lactating Women

Pregnancy: Classified as Pregnancy Category C; use only when clearly necessary.

Lactation: Either breastfeeding or the drug should be discontinued.

Patients with Photosensitive Diseases

Lupus erythematosus.

Porphyria.

Xeroderma pigmentosum.

Albinism.

History of melanoma.