Active ingredient: oral contraceptives
The relationship between oral contraceptives and metabolism of ethanol in women was examined in a group of 40 social drinkers aged 21 to 30 years. Twenty women taking oral contraceptives and 20 other women who were not taking oral contraceptives took a moderate dose of ethanol (0.52 g / kg) during the menstrual , intermenstrual and premenstrual phase of the cycle. The group of women taking oral contraceptives showed a significant decrease in the rate of elimination of ethanol (105 mg/kg/h) in comparation with women who were not taking oral contraceptives (121 mg/kg/h, p <0.005).
These results were consistent across all three phases of the menstrual cycle and also when body mass index was taken in count.
The decreased rate of ethanol metabolism in women taking oral contraceptives is consistent with data from other oral contraceptives drugs that also have a decrease in metabolic rates in women taking contraceptives.
These results indicate the need for caution regarding the possible interaction of oral contraceptives with alcohol .
The results of another study suggest that oral contraceptive use may induce some kind of tolerance to ethanol. The researchers suggest that, at least, women who use oral contraceptives should try not to drink more than usual.
A group of 20 women receiving oral contraceptives was compared with other with similar features but not taking birth control pills. In the first group occurred a significant elevation of acetaldehyde concentration respect to the 2nd group. The authors consider that women with high levels of steroids, either by oral contraceptives or pregnancy, have a higher risk of toxic effects from ingestion of alcohol.
In patients receiving ethinylestradiol, no changes were observed in the pharmacokinetics of alcohol by effect of estrogen. 
Consuming large amounts of alcohol has been associated with menstrual irregularities, including anovulatory cycles, recurrent amenorrhea and early menopause. In addition, moderate alcohol consumption appears to increase the risk of spontaneous abortion and breast cancer. These effects should, at least in part, to changes in hormone levels produced by alcohol
It has been published the case of a patient of 33 years, that consumed daily a liter of beer and suffered a heart attack three weeks after start taking oral contraceptives. These drugs reduce the level of antithrombin III and the blood fibrinolytic activity, resulting in a blood's hypercoagulation.
Blood pressure correlates with the combined use of oral contraceptives and alcohol. In one study, the values of systolic blood pressure were about 8 mm Hg higher in women taking oral contraceptives and drank more alcohol compared with women not taking oral contraceptives and consumed minimally alcoholic beverages .
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