Drug-metabolizing enzyme system hepatic microsomal, effects

As noted above, many of the AEDs induce hepatic microsomal enzyme systems and thus reduce the effectiveness of hormonal contraceptives. Women taking AEDs that may reduce the effectiveness of hormonal contraceptives should be encouraged to also use other forms of birth control. Due to induction or inhibition of sex hormone metabolism and changes in binding of hormones to sex hormone binding globulin, some AEDs may reduce fertility. For example, valproate has been associated with a drug-induced polycystic ovarian syndrome. Women who experience difficulties with fertility should seek the advice of health care professionals with expertise in fertility. 

Various substituted and unsubstituted methylenedioxy derivatives of apomorphine and V-n-propylnorapomorphine have been studied by Baldessarini et and one of these, 10,11 -methylenedioxy-V-n-propylnorapomorphine, was found to be both a long-acting and an orally efficient prodrug (Fig. 33.28). The oral activity of the compound can be ascribed to the protection of the catechol system from the first-pass effects by the methylenedioxy group. The conversion to the free catechol is possible thanks to the hepatic microsomal enzymes (see Chapters 28 and 29 on drug metabolism). 

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