Medoff Jeffrey, Katz Seymour, Malik Pramod, Pambianco Daniel, Pruitt Ronald, Poulos John, Rank Jeffrey, Rose Martin
Vital Re:Search, Greensboro, North Carolina, USA.
Clin Ther. 2004 Sep;26(9):1479-91. doi: 10.1016/j.clinthera.2004.09.007.
The tablet formulation of sodium phosphate (NaP) is a prescription osmotic purgative that has been marketed since 2001. The use of NaP tablets in patients with constipation has not been studied previously.
This study assessed the tolerability and efficacy of 28 days of therapy with NaP tablets (1.5 g NaP/tablet) in patients with chronic constipation.
Adults with functional constipation or constipation-predominant irritable bowel syndrome and Z-3 spontaneous bowel movements (BMs) during the 7-day screening/baseline period were eligible for this open-label, dose-ranging study. Patients were randomized to receive starting doses of 4 NaP tablets (group A) or 8 NaP tablets (group B) each morning for 28 days. After a minimum of 48 hours, the NaP dose could be titrated upward (in the case of no BM or no relief of symptoms) or downward (in the case of a predefined excess laxative response) by 2 tablets/d to a minimum of 2 tablets/d or a maximum of 12 tablets/d. Patients kept a diary of their BMs and gastrointestinal symptoms. A serum chemistry panel was obtained weekly. The primary end points were the constipation response (based on the change from baseline in weekly number of BMs) and the global sense response (based on daily scores for the patient's overall sense of change in their bowel problems).
At randomization, there were 18 patients in group A and 25 in group B. Of these, 40 patients (16 group A, 24 group B) had > or 7 days of diary information while taking study treatment and were evaluable for efficacy. The constipation response rate was 100% in group A and 95.8% in group B, and the respective global sense response rates were 68.8% and 79.2%. Four patients in group B withdrew due to adverse events, none of which were serious. Five patients had occasional hypokalemia that required no treatment. Changes from baseline in serum concentrations of calcium, inorganic phosphorus, and potassium were not clinically significant and did not require treatment.
In this small study, NaP tablets taken daily were generally well tolerated (particularly in the low-dose group) and produced prompt relief of constipation--generally within the first week of treatment--that was sustained over the 28-day treatment period. A reasonable starting dose appears to be 2 to 4 tablets (3-6 g NaP) daily.
磷酸钠（NaP）片剂是一种自2001年上市的处方渗透性泻药。此前尚未对便秘患者使用NaP片剂进行研究。
本研究评估了NaP片剂（1.5克NaP/片）治疗慢性便秘患者28天的耐受性和疗效。
在7天筛查/基线期内有功能性便秘或便秘型肠易激综合征且自发排便（BM）次数为Z-3次的成年人有资格参加这项开放标签、剂量范围研究。患者被随机分为两组，每天早上分别服用起始剂量的4片NaP片剂（A组）或8片NaP片剂（B组），持续28天。至少48小时后，若未排便或症状未缓解，NaP剂量可向上滴定（增加2片/天）；若出现预先定义的过度泻药反应，剂量可向下滴定（减少2片/天），最低为2片/天，最高为12片/天。患者记录其排便情况和胃肠道症状。每周进行一次血清化学检测。主要终点是便秘反应（基于每周排便次数相对于基线的变化）和整体感觉反应（基于患者对肠道问题总体变化的每日评分）。
随机分组时，A组有18名患者，B组有25名患者。其中，40名患者（A组16名，B组24名）在接受研究治疗期间有超过或等于7天的日记信息，可进行疗效评估。A组的便秘缓解率为100%，B组为95.8%，各自的整体感觉反应率分别为68.8%和79.2%。B组有4名患者因不良事件退出，均不严重。5名患者偶尔出现低钾血症，无需治疗。血清钙、无机磷和钾浓度相对于基线的变化在临床上无显著意义，无需治疗。
在这项小型研究中，每日服用NaP片剂通常耐受性良好（尤其是低剂量组），并能迅速缓解便秘——通常在治疗的第一周内——且在28天治疗期内持续有效。合理的起始剂量似乎是每天2至4片（3 - 6克NaP）。
