Edelman J, Biggs D F, Jamali F, Russell A S
Clin Pharmacol Ther. 1984 Mar;35(3):382-6. doi: 10.1038/clpt.1984.47.
Twelve patients with either rheumatoid or psoriatic arthritis were injected with a 10-mg bolus dose of methotrexate (MTX) either intramuscularly (n = 6) or intravenously (n = 6) and the MTX concentration in their sera was determined by radioimmunoassay. MTX concentration--time data fitted triexponential equations. Doses injected intramuscularly were rapidly and completely absorbed. There were no significant intergroup differences in drug mean t 1/2, volume of distribution, and total body clearance. In nine patients serum MTX concentrations remained above the suggested critical level of 0.01 mumol throughout the 24-hr study irrespective of the route of administration, but MTX did not cumulate in the serum. We conclude that the behavior of low doses of MTX in patients with arthritis closely resembles the pattern in patients receiving intermediate and high doses for the treatment of neoplasia.
12名类风湿性关节炎或银屑病关节炎患者接受了10毫克甲氨蝶呤（MTX）的静脉推注，其中6人通过肌肉注射，6人通过静脉注射，然后通过放射免疫测定法测定他们血清中的MTX浓度。MTX浓度-时间数据符合三指数方程。肌肉注射的剂量迅速且完全被吸收。药物的平均半衰期、分布容积和全身清除率在组间没有显著差异。在9名患者中，无论给药途径如何，在整个24小时的研究中血清MTX浓度均保持在建议的临界水平0.01微摩尔以上，但MTX并未在血清中蓄积。我们得出结论，低剂量MTX在关节炎患者中的行为与接受中高剂量MTX治疗肿瘤的患者模式非常相似。
