Psoralens adverse effects

There is a bath PUVA and an oral PUVA. Bath PUVA therapies involve soaking in a bath of psoralens liquid for 15 minutes prior to UVA treatment. Oral PUVA involves taking an oral psoralens capsule the day prior to a UVA treatment. Oral psoralens such as methoxsalen cause nausea in many patients. Other adverse effects of PUVA include photosensitivity, which necessitates the use of eye protection and UVA-blocking sunscreen for 24 hours after a PUVA treatment macular melanosis at exposed sites (PUVA lentigines) and increased risk of skin cancers, especially squamous cell carcinoma.21... 

Bathwater delivery of psoralens ( Bath PUVA ) is an attractive alternative to oral administration, since it virtually lacks systemic adverse effects and the rapid decline of photosensitivity after bath PUVA enables the patient to pursue daily activities without restrictions (4). Trioxysalen bath PUVA does not have carcinogenic effects (5). 

Some adverse effects of the various psoralens have been reported. Re-pigmentation of the skin brought about by psoralen is found to be unreliable [567] maybe the cause of this failure is the absence of melanocytes in pathological conditions of the skin [545, 546]. 

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