Lake C R, Zaloga G, Bray J, Rosenberg D, Chernow B
Department of Psychiatry, Uniformed Services University of the Health Sciences, F. Edward Hebert School of Medicine, Bethesda, Maryland 20814-4799.
Am J Med. 1989 Apr;86(4):427-32. doi: 10.1016/0002-9343(89)90341-0.
Reports of severe adverse reactions following the ingestion of single (75 mg) or double doses of the sympathomimetic drug phenylpropanolamine (PPA), with and without caffeine, prompted us to undertake a study of the effects of five drug preparations (75 mg PPA, 150 mg PPA, 75 mg PPA plus 400 mg caffeine, 400 mg caffeine, and placebo) in 16 resting, normotensive subjects. The study was of a double-blind, randomized, crossover design. Each subject consented to take the five drug preparations on different study days, which were separated by at least 48 hours.
Compared with blood pressure (BP) values obtained after placebo ingestion, significant BP increases occurred over several hours following 150 mg PPA and after 75 mg PPA plus 400 mg caffeine. Significant BP increases after ingestion of 75 mg PPA and after 400 mg caffeine were less frequent. The mean peak BP following 150 mg PPA was 173 +/- 9/103 +/- 4 mm Hg, compared with 148 +/- 4/97 +/- 3 mm Hg after the other three active preparations; after placebo, peak BP reached 137 +/- 8/85 +/- 5 mm Hg.
These results indicate that 150 mg PPA (the amount in two diet aids) substantially elevates BP. Our findings may explain some of the recent case reports of nontraumatic intracranial hemorrhage in young, healthy persons ingesting PPA at recommended or minimally greater dosages. We suggest physicians inform patients who are likely consumers of PPA (i.e., those with allergies, those with eating disorders, overweight persons, women during the postpartum period) and patients at risk for stroke (i.e., the elderly and hypertensive patients) of the risks of taking more than the recommended amounts of PPA and of combining caffeine with PPA.
目的、患者及方法：有报告称，摄入单剂量（75毫克）或双剂量的拟交感神经药物苯丙醇胺（PPA），无论是否含有咖啡因，均会出现严重不良反应，这促使我们开展了一项研究，观察五种药物制剂（75毫克PPA、150毫克PPA、75毫克PPA加400毫克咖啡因、400毫克咖啡因和安慰剂）对16名静息、血压正常受试者的影响。该研究采用双盲、随机、交叉设计。每位受试者同意在不同的研究日服用这五种药物制剂，研究日之间至少间隔48小时。
与服用安慰剂后的血压（BP）值相比，服用150毫克PPA以及75毫克PPA加400毫克咖啡因后数小时内，血压显著升高。服用75毫克PPA和400毫克咖啡因后血压显著升高的情况较少见。服用150毫克PPA后的平均血压峰值为173±9/103±4毫米汞柱，而服用其他三种活性制剂后的血压峰值为148±4/97±3毫米汞柱；服用安慰剂后，血压峰值为137±8/85±5毫米汞柱。
这些结果表明，150毫克PPA（两种减肥药中的含量）会大幅升高血压。我们的研究结果或许可以解释近期一些关于年轻健康人群按推荐剂量或略高于推荐剂量服用PPA后出现非创伤性颅内出血的病例报告。我们建议医生告知可能服用PPA的患者（即过敏患者、饮食失调患者、超重者、产后女性）以及有中风风险的患者（即老年人和高血压患者），服用超过推荐剂量的PPA以及将咖啡因与PPA合用的风险。
