Water potentiates the pressor effect of ephedra alkaloids
Water potentiates the pressor effect of ephedra alkaloids
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DOI：
10.1161/01.cir.0000126283.99195.37
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发表时间：
2004-04-20
期刊：
影响因子：
37.8
通讯作者：
Biaggioni, I
中科院分区：
文献类型：
--
作者：
Jordan, J;Shannon, JR;Biaggioni, I
背景 - 在非处方制剂中使用麻黄生物碱与潜在的严重脑血管事件有关。由于其与出血性中风的潜在关联，苯丙醇胺已在很大程度上被伪麻黄碱取代，但尚不清楚这是否确实是一种更安全的替代品。了解麻黄生物碱对心血管的影响非常重要，但这些影响通常被压力反射缓冲机制所掩盖。因此，我们研究了麻黄生物碱对自主神经功能障碍患者的影响，并探讨了它们与水摄入的潜在相互作用。方法和结果 - 在 13 名因自主神经衰竭而导致压力感受反射功能受损的受试者中，测定了苯丙醇胺或伪麻黄碱单独使用以及与水合用对心血管的影响。苯丙醇胺，12.5 至 25 mg PO，90 分钟后收缩压 (SBP) 增加 21 +/- 14 mm Hg。然而，当摄入 16 盎司室温自来水时，苯丙醇胺会使收缩压增加 82 +/- 2 毫米汞柱。伪麻黄碱，30 毫克口服，与 16 盎司水一起服用时，收缩压平均增加 52 +/- 9 毫米汞柱，最高可达 88 毫米汞柱。结论 - 麻黄生物碱显着增加压力反射功能受损个体的血压。同时摄入麻黄生物碱和水会导致血压大幅升高。如果谨慎使用，这种相互作用可能有益于治疗直立性低血压。另一方面，考虑到正常人的压力感受反射功能差异很大，并且在多种医疗条件下会受到损害，它可能会导致与使用麻黄生物碱相关的心血管并发症。
Background - The use of ephedra alkaloids in over-the-counter preparations has been associated with potentially serious cerebrovascular events. Because of its potential association with hemorrhagic strokes, phenylpropanolamine has been largely substituted for by pseudoephedrine, but it is not clear whether this is indeed a safer alternative. It would be important to understand the cardiovascular effects of ephedra alkaloids, but these are normally masked by baroreflex buffering mechanisms. We therefore investigated the effects of ephedra alkaloids in patients with autonomic impairment and explored their potential interaction with water ingestion.Methods and Results - The cardiovascular effects of phenylpropanolamine or pseudoephedrine, alone and in combination with water, were determined in 13 subjects with impairment of baroreflex function due to autonomic failure. Phenylpropanolamine, 12.5 to 25 mg PO, increased systolic blood pressure (SBP) by 21 +/- 14 mm Hg after 90 minutes. However, when ingested with 16 oz of room temperature tap water, phenylpropanolamine increased SBP by 82 +/- 2 mm Hg. Pseudoephedrine, 30 mg PO, increased SBP on average 52 +/- 9 mm Hg when taken with 16 oz of water and by as much as 88 mm Hg.Conclusions - Ephedra alkaloids increase blood pressure significantly in individuals with impaired baroreflex function. Concomitant ingestion of ephedra alkaloids and water produced a greater increase in blood pressure. If used cautiously, this interaction can be beneficial in the treatment of orthostatic hypotension. On the other hand, it could contribute to the cardiovascular complications associated with the use of ephedra alkaloids, given that baroreflex function varies widely in normal individuals and is impaired in several medical conditions.