Dietary influences on 8-MOP plasma levels in PUVA patients with psoriasis.

To study the effect of diet on 8-MOP plasma levels, these levels were measured three times in twenty PUVA patients with psoriasis; while fasting, after a low-fat breakfast, and after a fat-rich breakfast. No significant differences were found between the maximal 8-MOP plasma levels in the fasting condition and the levels after the low-fat breakfast, both peaking 2 h after ingestion. After the fat-rich breakfast, however, the 8-MOP plasma levels were not only significantly lower at 2 h but also peaked later, reaching their maximum at 3-4 h after intake. The drug should therefore be given in a dietetically standardized way. This raises the question whether some cases of therapy resistance can be dietetically influenced.