Interactions between nuvigil(armodafinil) and Camila (norethindrone)
norethindrone and armodafinil (Moderate Drug-Drug)
ADDITIONAL CONTRACEPTION RECOMMENDED: Coadministration with modafinil (the racemate) or armodafinil (the R-enantiomer) may decrease the plasma concentrations of ethinyl estradiol and other contraceptive hormones. The mechanism involves induction of CYP450 3A4-mediated metabolism by modafinil and armodafinil. In female volunteers treated chronically with an oral contraceptive containing ethinyl estradiol (0.035 mg) and norgestimate (0.18 to 0.25 mg), an 18% reduction in mean ethinyl estradiol systemic exposure (AUC) from baseline was observed in 16 subjects receiving modafinil (200 mg once daily for 7 days, then 400 mg for 21 days) compared to a 4% reduction in 18 subjects receiving placebo. The mean peak plasma concentration (Cmax) of ethinyl estradiol was also reduced by 11% versus 5% from baseline, respectively. The clinical significance of these alterations is unknown. In the study, pharmacodynamic effects as measured by plasma levels of FSH and LH showed no statistically significant differences between treatment groups before or after treatment with modafinil versus placebo. However, pharmacokinetic effects and interactions involving ethinyl estradiol are often subject to a high degree of interpatient variability, and the clinical significance may be increased in certain susceptible patients.
MANAGEMENT: Women using hormonal contraceptives (including depot and implantable contraceptives) should be advised of the risk of breakthrough bleeding and unintended pregnancy during concomitant therapy with modafinil or armodafinil. Alternative or additional methods of birth control are recommended during and for one month after treatment with modafinil or armodafinil.
