A woman has been treated for a few years with Naprosyn (naproxen) due to rheumatic pain. Her therap

Fråga: A woman has been treated for a few years with Naprosyn (naproxen) due to rheumatic pain. Her therapy was changed to Miranax (naproxen sodium). After about six months she developed blisters on the dorsal side of the hands. Can these blisters be caused by treatment with naproxen sodium? After healing, can a different NSAID be chosen for this patient?

Sammanfattning: There are reports on skin reactions caused by naproxen in the literature. Several cases describe naproxen induced pseudoporphyria with blisters on the dorsal sides of the hands. In these cases, solar exposure was a crucial factor since the blisters disappeared when naproxen was withdrawn. There are no reports indicating a cross reaction between different NSAID:s in this case.

Svar: It is not very likely that the change of therapy from naproxen to naproxen sodium has caused the patient´s blisters. The manufacturer, Syntex, also confirms that it is not very likely that there are any differences in side effects of these two preparations (1).

Skin reactions caused by naproxen have been reported to SADRAC in approximately 200 cases. Fifty four of these concern urticaria, sixtyfive exanthem, six erythema multiforme, four bullous dermatitis, five exanthem vesico bollous, six mucocutaneous syndrome and also one report regarding a pempfigoid reaction (2).

There are several reports in the literature describing naproxen induced bullous photodermatitis (pseudoporphyria) with recurrent blisters and fragility of the skin of hands and face. In pseudoporphyria, the patient has the skin manifestations of porphyria cutena tarda, but no biochemical evidence of abnormal porphyrins (3,4). The described symptoms seem to occur after a long term treatment with naproxen. One article reports pseudoporphyria with formation of bullae and vulnerability of skin exposed to light - particularly the backs of the hands. This reactions was envoked by different drugs (ie ibuprofen and naproxen) (5).

Five cases of naproxen induced pseudoporphyria were reported and in all these cases solar exposure was a crucial factor. After withdrawal of naproxen no further blisters developed (4).

When it comes to cross reactions with other NSAID:s, the risk is obvious with a side effect like asthma. However, it is possible that bollous dermatitis is caused by cell mediated immunity towards a certain drug molecule rather than prostaglandin synthesis inhibition (6). We have not found any reports in the literature indicating that related drugs should have a greater risk of giving bullous dermatitis.

With this particular patient, naproxen should be regarded as contraindicated. If needed, an NSAID with a different chemical structure could be tried. We recommend that the case is reported to SADRAC.