There is a growing interest in the psychiatric properties of the
dissociative anesthetic ketamine, as single doses have been shown to
have fast-acting mood-enhancing and anxiolytic effects, which persist
for up to a week after the main psychoactive symptoms have diminished.
Therefore, ketamine poses potential beneficial effects in patients with
refractory anxiety disorders, where other conventional anxiolytics have
been ineffective. Ketamine is a non-competitive antagonist of the
N-methyl-D-aspartate (NMDA) glutamate receptor, which underlies its
induction of pain relief and anaesthesia. However, the role of NMDA
receptors in anxiety reduction is still relatively unknown. To fill this
paucity in the literature, this systematic review assesses the evidence
that ketamine significantly reduces refractory anxiety and discusses to
what extent this may be mediated by NMDA receptor antagonism. We
highlight the temporary nature of the anxiolytic effects and discuss the
high discrepancy among the study designs regarding many fundamental
factors such as administration routes, complementary treatments, and
other treatments.
Ketamine Treatment for Refractory Anxiety: A systematic review
