石杉碱甲

 
Melting Point:  214~215℃
Soubility:  Soluble in Chloroform,Methanol,Ethanol,and slightly in water.
Appearance:  White or milk white powder, oderless.
Pharmacology Action: Huperzine A may have cognition-enhancing activity, can maintains acetylcholine levels for healthy cognitive function and promotes enhanced memory and cell to cell communication,it is potentially ward off the devastating effect of the memory-robbing disease Alzheimer's.
Dosage:Huperzine A is a highly potent compound with a recommended dose of only 100 to 200 micrograms twice a day for age-related memory loss. We recommend using it only under a doctor's supervision.
Safety Issues:Perhaps because it works so specifically, huperzine A appears to have few side effects. However, children, pregnant or nursing women, or those with high blood pressure or severe liver or kidney disease should not take huperzine A except on a doctor's recommendation. We also don't know for sure whether huperzine A interacts adversely with any drugs; however, it seems likely that huperzine might interact with drugs that function in a similar fashion (such as standard drugs for Alzheimer's Disease).

 熔点：214~215 ℃ 
溶解性：易溶于氯仿，溶于甲醇、乙醇，微溶于水
性状：白色或奶白色粉末，无味。
药理作用：本品系由石杉科植物千层塔[Huperzinaserrata(Thumb.)Trev]中提取的一种生物碱，是一强效的胆碱酯酶可逆性抑制剂，其作用特点与新斯的明相似，但作用维持时间比后者为长。动物实验表明，本品对真性胆碱酯酶具有选择性的抑制，抑制强度是假性胆碱酯酶的数千倍；抑制方式为竞争性和非竞争性的混合型抑制，与单纯竞争性抑制剂有显著不同；易通过血脑屏障进入中枢，兼具有中枢及外周治疗作用；有效时间长；从胃肠道吸收良好；安全指数大；稳定性好。是一种强效的可逆性AChE抑制剂，能改善老年性记忆功能减退，可显著提高AD患者的记忆、认知和行为功能，无明显不良反应，是治疗阿耳茨海默病的一个有前景的药物。
适应症：本品适用于良性记忆障碍、脑血管疾病、脑创伤、器质性精神障碍、外周血管阻塞性疾病、糖尿病神经病变、急慢性跟腱疼痛、运动性肌肉创伤。
不良反应：少数病人给药后见耳鸣、头晕、肌束颤动、出汗腹痛等，个别病人有瞳孔缩小、呕吐、大便增加、视力模糊、心率改变、流涎、思睡等不良反应，上述副反应的出现率，除恶心外均较新斯的明为低，且均可自行消失。严重者可用阿托品对抗。
注意事项：①禁用于心绞痛、支气管哮喘、机械性肠梗阻病人。②慎用于妊娠妇女。