Why Might Ketamine Infusion Therapy Work for Me?
Antidepressant therapy has been available for over 50 years, and its emergence was heralded as a major victory for medical science. Despite this success, many patients do not experience relief with antidepressants, with cumulative rates of remission standing at 67% (Rush et al 2006). This means, that on average, 33% of those treated fail to achieve any meaningful improvement in their depression symptoms.
Through a fortuitous discovery, ketamine was found to dramatically and rapidly alleviate depression in adults after receiving only one low-dose IV infusion (Berman et al. 2000). Later studies by Zarate et al. (2006) and Murrough et al. (2013) confirmed these findings in larger randomized controlled trials involving patients with treatment-resistant depression.
Ketamine acts on the NMDA receptor, antagonizing glutamate signaling. Both depression and prolonged stress are associated with atrophy of neurons and damage of synapse function (Kang et al. 2012). Prolonged stress induces changes in glutamate release and reuptake, leading to toxic levels of glutamate in the synapse. This, in turn, has a damaging effect on synapses, stripping the fine connections between nerves within the brain regions regulating mood. Evidence suggests that ketamine acts to block and reverse the damaging effect associated with toxic levels of glutamate and accelerates new synapse formation (Duman and Aghajanian 2012, Li et al. 2010).
Several trials consistently report rapid antidepressant effects beginning within 4 hours of IV infusion (Abdallah et al. 2015; Berman et al. 2000; Bessa et al. 2009,2013; Caddy et al. 2014; Duman and Aghajaninan 2012; Fond et al. 2014; Kang et al. 2012). In the short term, patient response rates were found to range from 43% up to 90% (Phelps et al. 2009, aan het Rot et al. 2008). Some sustained effects were seen for as long as 28 days after a single infusion (Ibrahim et al. 2012, Zarate et al. 2006).
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