Rajput A H, Stern W, Laverty W H
Neurology. 1984 Aug;34(8):991-6. doi: 10.1212/wnl.34.8.991.
Levodopa is the most useful drug for treatment of Parkinson's disease today. But after continued use for several years, the effectiveness declines, and the undesirable side effects become more frequent, leading to unsatisfactory control. Once the treatment failure emerges, further management is difficult and often unsuccessful. One alternative for preventing side effects and treatment failure is to use a low dose. We are reporting our 12-year experience on uninterrupted treatment with levodopa, 3 grams (approximate) daily. The improvement was comparable with the best reports on higher dosage, and the side effects were significantly less frequent. The frequency of dyskinesia and on-off phenomena showed a strong correlation with duration of treatment. Psychiatric side effects were more common on treatment, but frequency of dementia did not correlate with duration of therapy. Improvement reached a peak after 6 months and remained statistically significant for 3.5 years. By the end of 5 years, the disability profile in the group was similar to that prior to levodopa treatment. So far, there is no satisfactory method for preventing treatment failure. From our observations, low dosage of levodopa is a desirable alternative, but not the answer to therapeutic failure. We recommend that levodopa use be delayed until the patient has a functional and/or psychological handicap that cannot be satisfactorily controlled with less potent antiparkinsonian agents.
左旋多巴是当今治疗帕金森病最有效的药物。但连续使用数年之后，其疗效会下降，不良副作用会更加频繁，导致控制效果不尽人意。一旦出现治疗失败，后续处理就会很困难，而且往往不成功。预防副作用和治疗失败的一种方法是使用低剂量。我们报告了我们连续12年每天使用约3克左旋多巴进行不间断治疗的经验。其改善效果与关于高剂量的最佳报告相当，且副作用明显更少。运动障碍和开关现象的发生频率与治疗持续时间密切相关。治疗期间精神方面的副作用更为常见，但痴呆的发生频率与治疗持续时间无关。改善在6个月后达到峰值，并在3.5年内保持统计学意义。到5年末，该组的残疾状况与左旋多巴治疗前相似。到目前为止，尚无预防治疗失败的令人满意的方法。根据我们的观察，低剂量的左旋多巴是一种理想的选择，但并非治疗失败的解决方案。我们建议推迟使用左旋多巴，直到患者出现功能和/或心理障碍，而使用效力较弱的抗帕金森病药物无法令人满意地控制这些障碍时再使用。
