在服用扑热息痛后炔雌醇的Auc增加22％。代谢物硫酸炔雌醇相应减少。同时服用扑热息痛时左旋甲基炔诺酮的血浆浓度不变。相互作用使炔雌醇达到比避孕目的所需更高的浓度。当给予治疗剂量扑热息痛时首先与硫酸和葡萄糖醛酸结合而被代谢。口服避孕药物炔雌醇也与硫酸大量结合。由体外模型试验证明,扑热息痛的存在可降低炔雌醇的硫酸 Ethinyl estradiol increased Auc by 22% after taking paracetamol. Ethinyl estradiol metabolites decreased accordingly. Paracetamol at the same time when the plasma concentration of levonorgestrel unchanged. Interaction allows ethinylestradiol to reach higher concentrations than required for contraception. Paracetamol is first metabolized when it is administered in combination with sulfuric acid and glucuronic acid. Ethinyl estradiol, an oral contraceptive, is also bound in large quantities to sulfuric acid. Proved by in vitro model tests, the presence of paracetamol can reduce ethinyl estradiol sulfate