After consulting on the treatment of hundreds of patients with ketamine, I have learned that the road to recovery can vary, dramatically.
Most of the patients with whom I have interacted report relief after the very first infusion, which increases their mood and decreases their anxiety and relieves them of the sense that life may not be worth living.
Other patients find this relief after the second or third or even the fourth infusion.
A minority of patients receive six infusions, without significant results, but then, over the ensuing days and weeks, report that their activity levels have increased, that their optimism has returned and that their concentration levels and cognitive abilities seem to have returned toward normal.
A number of my patients have repeated the series of six infusions and seen further benefits.
Why would it be that the positive effects of ketamine might be both immediate and longer-term?
The explanation may well be that ketamine’s effects result not only from influencing neurotransmitters, such as blocking glutamate. Ketamine also apparently increases the connectivity between nerve cells in the brain—literally causing more activity at the synapses where nerve cells communicate with one another. The mechanism for this increased connectivity is not known, but may be due to ketamine fueling actual structural rebuilding of the synapse, which could take some amount of time.
Ketamine is the most exciting development in treating depression and anxiety that I have encountered in twenty years practicing psychiatry. No doubt, it will take much research to fully understand its mechanisms of action. Theories about the actual mechanism of action of oral antidepressants are still being debated, decades after their introduction.
Today, however, we psychiatrists clearly have a miraculous new tool for healing patients in our therapeutic armamentarium.