RESUMEN
BACKGROUND: The aims of this research were to document the nature of oxidative stress (OS) while taking an estrogen/progestagen-combined oral contraceptive (OC) and to evaluate the action of two different products composed of a combination of antioxidant, vitamins and natural products in physiological quantity and classified as antioxidant/food supplement. For this reason, the two products are classified as physiological modulators (PM), able to restore the balance between antioxidants and reactive oxygen species in the organism. STUDY DESIGN: The Reactive Oxygen Metabolites-derived compound test, a photometric assay that measures the hydroperoxides levels in biological fluids, was used to determine the OS. OS was analyzed every 3 days (from t(1) to t(27)) for 28 days on 10 healthy volunteers during three successive OC treatment cycles with a contraceptive (Microgynon®: ethinylestradiol 50 mcg plus levonorgestrel 125 mcg). In the first cycle, the OC was administered by itself; in the successive two cycles, the OC was administered in association in an open crossover study with two different types of PMs with antioxidant action. The main difference in the composition of the two products is the presence/absence of catechins from green tea. RESULTS: With just OC treatment, all the volunteers showed an increase in the OS values from 240±22.3 (mean±SD) Carratelli Units. (normal value) up to values >400 Carratelli Units (severe OS), then returned to normal when the OC therapy was suspended. The concomitant use of the two PMs showed that only the product containing green tea catechins was able to reduce the OS values, on average, by approximately 50% (t test p<.05). CONCLUSION: We conclude that to control the OS generated by OC, specific types of physiological modulators are needed.
Asunto(s)
Antioxidantes/administración & dosificación , Anticonceptivos Orales Combinados/metabolismo , Etinilestradiol/metabolismo , Levonorgestrel/metabolismo , Estrés Oxidativo , Adulto , Estudios Cruzados , Suplementos Dietéticos , Combinación de Medicamentos , Femenino , Humanos , Vitaminas/administración & dosificaciónRESUMEN
PURPOSE: St John's wort (Hypericum perforatum) is an herbal remedy that is widely used in the treatment of depression. Recent clinical data have demonstrated that St John's wort extracts interfere with the action of various drugs and possibly also with combined oral contraceptives. Therefore, we investigated the effects of a St John's wort extract (Ze 117) with low hyperforin content on the pharmacokinetics of ethinylestradiol and 3-ketodesogestrel. METHOD: Sixteen healthy female volunteers, who had taken a low-dose oral contraceptive (Lovelle contains 0.02 mg ethinylestradiol + 0.15 mg desogestrel) for at least 3 months, participated in the study. Pharmacokinetic data (AUC, C(max), t(max)) were determined the day before (reference) and after (test) a 14-day period of Ze 117 intake (250 mg twice daily). RESULTS: Before the co-administration of Ze 117 on day 7, the geometric mean (geometric coefficient of variation) for the AUC(0-24) of ethinylestradiol was 152.53 pg.h/ml (87.39%) and after co-administration on day 21 it was 196.57 pg.h/ml (78.14%). The respective values for ketodesogestrel were 36.37 pg.h/ml (34.18%) and 41.12 pg.h/ml (34.36%). The mean of individual ratios (reference-to-test) of log-transformed AUC values (90% confidence interval) were 0.951 (0.915-0.986) for ethinylestradiol and 0.968 (0.944-0.992) for ketodesogestrel indicating a small gain [corrected] in bioavilability, but bioequivalence nevertheless. CONCLUSION: These results indicate that the recommended dose of the hypericum extract Ze117, which has a low hyperforin content, does not interact with the pharmacokinetics of the hormonal components of the low-dose oral contraceptive.
Asunto(s)
Anticonceptivos Orales Combinados/farmacocinética , Desogestrel/farmacocinética , Etinilestradiol/farmacocinética , Extractos Vegetales/farmacocinética , Administración Oral , Adulto , Área Bajo la Curva , Anticonceptivos Orales Combinados/administración & dosificación , Anticonceptivos Orales Combinados/metabolismo , Desogestrel/administración & dosificación , Desogestrel/metabolismo , Etinilestradiol/administración & dosificación , Etinilestradiol/metabolismo , Femenino , Interacciones de Hierba-Droga , Humanos , Hypericum , Extractos Vegetales/administración & dosificación , ComprimidosRESUMEN
OBJECTIVES: The popular herbal remedy St John's wort is an inducer of cytochrome P450 (CYP) 3A enzymes and may reduce the efficacy of oral contraceptives. Therefore we evaluated the effect of St John's wort on the disposition and efficacy of Ortho-Novum 1/35 (Ortho-McNeil Pharmaceutical, Inc, Raritan, NJ), a popular combination oral contraceptive pill containing ethinyl estradiol (INN, ethinylestradiol) and norethindrone (INN, norethisterone). METHODS: Twelve healthy premenopausal women who were using oral contraception (>3 months) received a combination oral contraceptive pill (Ortho-Novum 1/35) for 3 consecutive 28-day menstrual cycles. During the second and third cycles, the participants received 300 mg St John's wort 3 times a day. The serum concentrations of ethinyl estradiol (day 7), norethindrone (day 7), follicle-stimulating hormone (days 12-16), luteinizing hormone (days 12-16), progesterone (day 21), and intravenous and oral midazolam (days 22 and 23) were determined in serial blood samples. The incidence of breakthrough bleeding was quantified during the first and third cycles. RESULTS: Concomitant use of St John's wort was associated with a significant (P <.05) increase in the oral clearance of norethindrone (8.2 +/- 2.7 L/h to 9.5 +/- 3.4 L/h, P =.042) and a significant reduction in the half-life of ethinyl estradiol (23.4 +/- 19.5 hours to 12.2 +/- 7.1 hours, P =.023). The oral clearance of midazolam was significantly increased (109.2 +/- 47.9 L/h to 166.7 +/- 81.3 L/h, P =.007) during St John's wort administration, but the systemic clearance of midazolam was unchanged (37.7 +/- 11.3 L/h to 39.0 +/- 10.3 L/h, P =.567). Serum concentrations of follicle-stimulating hormone, luteinizing hormone, and progesterone were not significantly affected by St John's wort dosing (P >.05). Breakthrough bleeding occurred in 2 of 12 women in the control phase compared with 7 of 12 women in the St John's wort phase. The oral clearance of midazolam after St John's wort dosing was greater in women who had breakthrough bleeding (215.9 +/- 66.5 L/h) than in those who did not (97.5 +/- 37.2 L/h) (P =.005). CONCLUSION: St John's wort causes an induction of ethinyl estradiol-norethindrone metabolism consistent with increased CYP3A activity. Women taking oral contraceptive pills should be counseled to expect breakthrough bleeding and should consider adding a barrier method of contraception when consuming St Johns wort.
Asunto(s)
Hidrocarburo de Aril Hidroxilasas/biosíntesis , Anticonceptivos Orales Combinados/metabolismo , Inducción Enzimática/efectos de los fármacos , Hypericum , Hipnóticos y Sedantes/farmacocinética , Mestranol/metabolismo , Midazolam/farmacocinética , Noretindrona/metabolismo , Oxidorreductasas N-Desmetilantes/biosíntesis , Preparaciones de Plantas/farmacología , Administración Oral , Adulto , Área Bajo la Curva , Hidrocarburo de Aril Hidroxilasas/metabolismo , Anticonceptivos Orales Combinados/sangre , Anticonceptivos Orales Combinados/farmacocinética , Citocromo P-450 CYP3A , Combinación de Medicamentos , Interacciones Farmacológicas , Femenino , Hormona Folículo Estimulante/sangre , Semivida , Humanos , Inyecciones Intravenosas , Ciclo Menstrual/efectos de los fármacos , Mestranol/farmacocinética , Tasa de Depuración Metabólica , Noretindrona/farmacocinética , Oxidorreductasas N-Desmetilantes/metabolismo , Preparaciones de Plantas/administración & dosificaciónRESUMEN
Once-a-month injectable contraceptives containing a progestogen and an estrogen have been developed that disrupt vaginal bleeding patterns less than the widely used progestogen-only preparations. Pharmacokinetic studies were undertaken of dosages and ratios of the progestogens and the respective estrogens. In Phase III clinical trials, annual pregnancy rates were below 0.4% for Mesigyna (norethisterone enanthate/estradiol valerate, Schering AG, Berlin, Germany) and below 0.2% for Cyclofem (MPA/E2C) (medroxyprogesterone acetate/estradiol cypionate, Aplicaciones Farmaceuticas, SA, Mexico and PT Tunggal, Indonesia). More than two-thirds of women had predictable, regular cycles, and discontinuation due to bleeding-related problems occurred less than half as often as with progestogen-only injectables. With MPA/E2C, return to fertility is similar to that observed with other hormonal or intrauterine methods, and both products have little effect on lipids or hemostasis. Introductory trials of MPA/E2C in 12000 women with 100000 woman-months of experience confirmed the high efficacy of the product in routine use. The use of MPA/E2C in a non-reusable injection device, Uniject (Becton Dickinson, Franklin Lakes, NJ) is discussed. Once-a-month hormonal contraceptives have been shown to provide a safe contraceptive option for all women and an alternative for women who wish to use injectable formulations that cause less disruption in vaginal bleeding and minimal side effects.