T. Terao et al., A puzzling case of seizures and visual hallucinations during clomipramine treatment with a high dose but causing a low serum concentration, ACT PSYC SC, 99(5), 1999, pp. 388-390
We present a puzzling case of a 25-year-old depressive man suffering from s
eizures and visual hallucinations during clomipramine treatment with a high
dose but causing a low serum concentration. We examined alleles of cytochr
ome P450 (CYP) isozymes. It was revealed that he was not an ultrarapid meta
bolizer for CYP2D6, and that the genotypes were homozygous for CYP2D6J and
heterozygous for CYP2C19(ml). Throughout the treatment period, his complian
ce was good. Since he was a smoker, it seems likely that his low clomiprami
ne level was due to smoking-induced CYP1A2 activity. These findings suggest
that smoking-induced CYP1A2 activity overcomes the possibly inhibiting eff
ects of homozygosity for CYP2D6J and heterozygosity for CYP2C19(ml), and th
at high-dose clomipramine is not always a direct cause of seizures.