碳酸对levothyroxine吸收的影响
N Singh1, P N Singh, J M Hershman
1Division of Endocrinology and Metabolism, Endocrinology 111D, VA Greater Los Angeles Healthcare System, 11301 Wilshire Blvd, Los Angeles, CA 90073. nsingh@ucla.edu
JAMA
|June 6, 2000
概括
碳酸显著降低了勒沃西的吸收,导致患者的甲状腺激素水平增加. 这种相互作用是由于levothyroxine对碳酸的吸附,可能会影响甲状腺激素替代疗法.
科学领域:
- 内分泌学 在内分泌学.
- 药理学 药理学是指药理学的学科.
- 药物相互作用 药物相互作用
背景情况:
- 同时使用碳酸和levothyroxine是常见的,特别是在绝经后的妇女.
- 缺乏关于碳酸和levothyroxine吸收之间的相互作用的系统研究.
- 由于广泛的联合处方,潜在的药物相互作用需要调查.
研究的目的:
- 为了研究碳酸对levothyroxine吸收的潜在干扰.
- 为了评估碳酸对甲状腺激素水平的影响.
- 了解碳酸和levothyroxine之间的相互作用机制.
主要方法:
- 一项前性队列研究,涉及20名接受稳定levothyroxine治疗的甲状腺功能低下患者.
- 在体外研究评估甲状腺素 (T4) 与碳酸结合.
- 测量自由T4,总T4,总trijodothyronine (T3) 和thyrotropin水平在基线,碳酸的同时使用期间,以及停止治疗后.
主要成果:
- 碳酸显著降低了平均自由T4和总T4水平.
- 在使用碳酸时,甲状腺蛋白水平的平均水平显著增加.
- 试验室研究表明,在酸性条件下,T4吸附于碳酸,这表明减少生物可用性的机制.
结论:
- 碳酸降低了勒沃西的吸收,并增加了铁激素水平.
- 在酸性环境中,levothyroxine对碳酸的吸附可能会降低其生物可用性.
- 在接受levothyroxine和碳酸的患者中,这种相互作用需要仔细考虑.
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