ALAS1 and acute intermittent porphyria: It has already been reported that CIM could reduce the activity of hepatic ALA-S induced by allylisopropylacetamide (AIA) in porphyric adult rats (Marcus et al, 1990) and that CIM could also be used in the prophylaxis of human acute intermittent porphyria by maintaining a baseline suppression of ALA-S activity (Horie et al, 1995; Rogers, 1997).