美金刚在帕金森症上的治疗推荐
金刚烷胺是一种很好的抗帕金森症药物，但其本身具有的副作用也是相当多的，而且最近的一些研究发现其对人类眼睛的视神经会有一定的损害，所以在应用金刚烷胺的同时必须监测患者的视力。
与金刚烷胺同属NMDA拮抗剂的美金刚（美金刚是金刚烷胺的衍生物），可以直接激动多巴胺受体，促进多巴胺释放，可以用于帕金森症的治疗（也用于帕症合并痴呆），剂量只需要每天5mg至20mg,为金刚烷胺的二十份之一，副作用也大幅下降。
以下是一个不能忍受左旋多巴及安坦的副作用的病人应用美金刚治疗帕症的经过（当然这不是唯一的一个病例，还有很多研究报告）。
因为目前安坦这类抗胆碱药物对于年青的震颤麻痹病人是有很好的效果，但长远会有影响认知的副作用，所以对于年长的病人并不推荐使用，而对于这一类病人，如果受体激动剂效果不理想，而又不想增加美多巴或息宁等左旋多巴的话，美金刚是值得一试的。
要注意的是，美金刚是对症治疗药物，可以改善生活质量，但不能改变帕症疾病进展（对减缓痴呆症的发展有一定作用）。
美金刚是SFDA批准的注册药物，在国内可以买到，厂家正是生产雷沙吉兰的以色列TEVA的合作公司丹麦伦北克（伦北克以研究神经系统药物出名）。
Southern Medical Journal:
June 2007 - Volume 100 - Issue 6 - p 617
doi: 10.1097/01.smj.0000257615.79559.3d
Special Sections: Letters to the Editor
Successful Treatment of Parkinson Disease with Memantine
Alisky, Joseph Martin MD, PhD
Free AccessArticle Outline
Author InformationMarshfield Clinic Research Foundation; Marshfield, WI; Marshfield Clinic Thorp Center; Thorp, WI
Memantine, a noncompetitive N-methyl-D-aspartate glutamate receptor inhibitor currently indicated for treatment of moderate Alzheimer disease, was originally developed for Parkinson disease and is still widely prescribed in Europe as an anti-Parkinsonian agent.1-3 Derived from the older drug amantadine, memantine dampens output from the subthalamic nucleus, potentiates dopamine release and attenuates degeneration of dopaminergic neurons.2-4 A case history presented here illustrates how memantine might have a productive therapeutic niche in the United States for Parkinson disease.
A 78-year-old woman with idiopathic Parkinson disease diagnosed one year before had mild cogwheel rigidity worse on the left side and intermittent pill-rolling tremors mainly in the left hand. She could do all basic activities of daily living and had no apparent functional limitations but was requesting treatment because her symptoms slowed her down. She had previously been tried on l-dopa/carbidopa but had developed unacceptable nausea and dizziness even from a starting dose. An anticholinergic agent such as trihexyphenidyl was considered, but she was already taking oxybutynin for overactive bladder and was adamant about not taking anything else that might worsen her memory. Therefore, she was prescribed a memantine titration pack, 5 mg daily and increased over a month to 10 mg twice daily. At her one-month follow-up, she reported improvement in initiation of activity, with no side effects of any kind. Physical examination confirmed that she had no visible tremor and almost complete abatement of the left-sided rigidity. She has been maintained on memantine 10 mg twice daily for the past year and continues to be satisfied with the medication.
Undoubtedly, memantine could be used for Parkinson disease both as monotherapy and as an adjunct to a multidrug regimen. In primary care practice, patients could be tried on the starter packs, and formal clinical trials would be easy to conduct as well. Ultimately, approval from the United States Food and Drug Administration (FDA) could be sought. Currently, the only FDA approved use for memantine is for Alzheimer disease, but other off-label uses besides Parkinson disease include vascular dementia, spasticity and neurogenic bladder.5 American physicians and researchers should give memantine for Parkinson disease some consideration, for new therapeutic options and improved outcomes.
Joseph Martin Alisky, MD, PhD
Marshfield Clinic Research Foundation(威斯康星州马什菲尔德诊所研究基金会）
Marshfield, WI
Marshfield Clinic Thorp Center
Thorp, WI.USA
