~-CAROTENE FOR ERYTHROPOIETIC PROTOPORPHYRIA?

o Increased Tolerance to Sunlight in Two Studies In an 8-week study on 160 patients ~-carotene ('Solatene') 15-180mg/ day increased the ability to tolerate sunlight by a factor of 3 or more in III of 133 patients with erythropoietic protoporphyria, in 9 of 27 with polymorphous light eruption and 2 of I 0 with other forms of photosensitivity [I]. All patients found the drug acceptable and none unduly disturbed by carotenodermia that developed after 4-6 weeks' therapy. One patient had a short-lived episode of diarrhoea. No significant changes were noted in routine laboratory tests. In all patients with erythropoietic protoporphyria blood and stool levels of porphyrin fluctuated, but remained above normal . In a retrospective survey on 16 patients with erythropoietic protoporphyria treated over 5 years with ~-carotene 50-2 OOmg/ day, all reported some increased exposure-time tolerance to sunlight [2]. Subjective clinical improvement failed to show any direct correlation with porphyrin levels in the blood or faeces, or any relationship with the estimation of the minimal response dose obtained by phototesting. Two patients relapsed while taking ~-carotene despite therapeutic plasma levels of the drug. No significant changes were found in laboratory tests, and plasma vitamin A levels remained within normal limits.

o But No Significant Effect in a Third In an II-month, randomised cross-over trial 14 patients with erythropoietic protoporphyria were given ~-carotene 1 OOmg / day or placebo [3]. No significant differences between the 2 preparations were noted by 5 patients, while 5 on ~-carotene and J on placebo thought symptoms were less. Two disliked the yellow skin colour produced with ~-carotene and I attributed nausea to the drug. Individual patient's weekly symptom-scores paired with the local mean hours of sunshine showed a significant positive correlation (p < 0.05). No abnormalities, apart from carotenaemia were noted in routine laboratory test levels. [I) Mathews-Roth, M.M. et a1.: Archives of Dermatology 113: 1229 (Sep 1977)

[2) Zaynoun, S.T. et al.: British Journal of Dermatology 97: 663 (Dec 1977)

13J Corbett, M.F. eta!. : Ibid 97: 655 (Dec 1977)

INPHARMA 22nd April. 1978 p9