ABSTRACT
We investigated the effect of antimycotic co-medication on the systemic exposure to etonogestrel (ENG) and ethinylestradiol (EE) released from the contraceptive vaginal ring, NuvaRing. Different formulations of miconazole nitrate and single as well as multiple dosing were investigated during two separate randomized, open-label, crossover studies. The first study recruited 12 women to compare the effects of co-use of NuvaRing and a single dose of antimycotic to NuvaRing alone. The second study recruited 14 women to compare the effects of multiple doses of an antimycotic vaginal suppository to an antimycotic vaginal cream equivalent. Co-administration of all three antimycotic formulations resulted in a slight increase in systemic exposure to ENG and EE over time, with suppositories having a more pronounced effect than a cream formulation in the multiple-dosing study. The increases in serum levels observed with the different antimycotic formulations are not expected to compromise NuvaRing's contraceptive efficacy or tolerability.
Subject(s)
Antifungal Agents/administration & dosage , Contraceptive Agents, Female/administration & dosage , Desogestrel/administration & dosage , Ethinyl Estradiol/administration & dosage , Miconazole/administration & dosage , Administration, Intravaginal , Adult , Antifungal Agents/pharmacokinetics , Candidiasis, Vulvovaginal/prevention & control , Contraceptive Agents, Female/pharmacokinetics , Cross-Over Studies , Desogestrel/pharmacokinetics , Dose-Response Relationship, Drug , Drug Interactions , Ethinyl Estradiol/pharmacokinetics , Female , Humans , Miconazole/pharmacokineticsABSTRACT
The effects of nonoxynol-9 on etonogestrel and ethinylestradiol release and absorption from NuvaRing were studied in 12 subjects for two cycles: one control and one interaction cycle (nonoxynol-9 was administered on day 8). Nonoxynol-9 had no effect on release or absorption and, consequently, serum levels. Therefore, nonoxynol-9 did not compromise the contraceptive efficacy of NuvaRing.
