Nefiracetam

Nefiracetam is a nootropic drug of the racetam family. Preliminary research suggests that it may possess certain antidementia properties in rats.<ref name=NPP2005>Template:Cite journal</ref>

Effects

Nefiracetam's cytoprotective actions are mediated by enhancement of GABAergic, cholinergic, and monoaminergic neuronal systems.Template:Citation needed Preliminary studies suggest that it improves apathy and motivation in post-stroke patients. It may also exhibit antiamnesia effects for the Alzheimer's type and cerebrovascular type of dementia.<ref>Template:Cite journal</ref><ref>Template:Cite journal</ref> In addition, research in animal models suggests antiamnesic effects against a number of memory impairing substances, including: ethanol, chlorodiazepoxide, scopolamine, bicuculline, picrotoxin, and cycloheximide.<ref name="Effects of nefiracetam on amnesia animal models with neuronal dysfunctions">Template:Cite journal</ref>

Pharmacology

Unlike other racetams, nefiracetam shows high affinity for the GABA_A receptor (IC₅₀) = 8.5 nM), where it is presumed to be an agonist.<ref name="pmid8061686">Template:Cite journal</ref><ref name="pmid2328758">Template:Cite journal</ref> It was able to potently inhibit 80% of muscimol binding to the GABA_A receptor, although it failed to displace the remaining 20% of specific muscimol binding.<ref name="pmid8061686" /><ref name="pmid2328758" /> Nefiracetam is able to reverse the amnesia caused by the GABA_A receptor antagonists picrotoxin and bicuculline in mice, although it failed to prevent seizures induced by these drugs.<ref name="pmid2328758" />

Concerns

Studies of long-term consumption of nefiracetam in humans and primates have shown it to have no toxicity.<ref name="Murasaki_1994">Template:Cite journal</ref><ref name="Otomo_1994_2">Template:Cite journal</ref> However, animals which metabolize nefiracetam differently from humans and primates are at risk for renal and testicular<ref>Template:Cite journal</ref><ref name=Shimomura>Template:Cite journal</ref> toxicity. Dogs especially are particularly sensitive, which has been shown to be caused by a specific metabolite, M-18 which isn't formed in humans.<ref name="Goto">Template:Cite journal</ref> Higher doses than those in dogs were needed to cause testicular toxicity in rats, although no toxicity was seen in monkeys. Additionally, there has been no evidence of toxicity during clinical trials.<ref name="Murasaki_1994"/><ref name="Otomo_1994_2"/>

See also

• Racetams
• Guvacine
• Phenibut