Hetey S K, Kleinberg M L, Parker W D, Johnson E W
Am J Hosp Pharm. 1980 Feb;37(2):235-7.
The ability of ascorbic acid to lower urinary pH in patients with spinal cord injury and neurogenic bladder was studied. Ascorbic acid (1 g four times daily) or placebo was administered for five days in a double-blind, crossover study to 20 patients with spinal cord injury and neurogenic bladder. Urine pH was measured for two days before and during administration of placebo or ascorbic acid. The mean decrease in urinary pH with ascorbic acid was 0.58, but this reduction was not statistically or clinically significant. Only 7 of 20 patients showed a mean urine pH of 5.5 or less (acidic) during treatment with ascorbic acid. The study suggests that an ascorbic acid dosage of 1 g four times daily should not be used to maintain an acidic urinary pH for control of urinary tract infections in patients with spinal cord injuries.
研究了抗坏血酸降低脊髓损伤和神经源性膀胱患者尿液pH值的能力。在一项双盲交叉研究中，对20例脊髓损伤和神经源性膀胱患者给予抗坏血酸（每日4次，每次1 g）或安慰剂，为期5天。在服用安慰剂或抗坏血酸之前和期间，测量两天的尿液pH值。抗坏血酸使尿液pH值平均降低0.58，但这种降低在统计学或临床上均无显著意义。20例患者中只有7例在服用抗坏血酸治疗期间尿液pH值平均为5.5或更低（呈酸性）。该研究表明，每日4次、每次1 g的抗坏血酸剂量不应用于维持酸性尿液pH值以控制脊髓损伤患者的尿路感染。
