Phototherapy burns and fluoxetine

A 43 year old woman with chronic plaque psoriasis was undergoing therapy with narrow band UVB. After 3 weeks of treatment she was seen to be improving. She had achieved a time of 5 min and this dose was repeated after 2 days. The accuracy ofthe setting was confirmed both by the operator and the patient. One hour after the second treatment at 5 min, she developed marked facial erythema and after 6 hours she had a painful generalized erythema and blisters on her neck. She was treated with rest, oral prednisolone, topical aloe vera gel and betamethasone diproprionate cream. The following day the patient reported blistering on her arms in the sites where she had previous psoriasis. She slowly improved but with considerable discomfort over the next week. The patient denied any extra sun exposure but in the 48 hours prior to the UV treatment she admitted to taking oxycodone, dextropropoxyphene and fluoxetine. A literature search [Medline (1994-1988) and the International Pharmaceutical Abstracts] failed to reveal any reports of photosensitivity with these agents but the Australian Adverse Drug Reaction Committee had reviewed two case reports of a possible photosensitivity with fluoxetine. Burning may occur more readily with narrow band UVB than with broad band UVB as a steeper erythema-dose curve has been reported with narrow band tubes.' Blistering limited to areas where psoriasis has been present has also been reported with narrow band UVB.̂ The role of a possible photosensitizing drug in this case could not be proved but no other explanation could be offered for the severe burn at a dose of UVB well tolerated 3 days before. This case highlights the importance of a drug history in patients undergoing phototherapy.