SSRI's for anxiety

SSRI's for anxiety

SSRI’s, TCA’s and MAOI’s all increase the neurotransmission of serotonin across the synapse. (Compare and contrast the mechanisms under SSRI’s, TCA’s and MAOI’s). The net result of these different mechanisms is however the same. The enhanced serotonin neurotransmission leads to down-regulation of post-synaptic receptors and subsequent changes in neuroplasticity. Over time, treatment will lead to a diminished response to sensory input by the amygdala, reduced physical manifestations of anxiety

(by modulating the response of the Locus Coeruleus, and the inhibiting activation of the HPA axis), and a decline in reliance on defensive behaviours (through modulation of gray matter neurotransmission). Due to their specificity (and thus decreased side effects) SSRI’s are considered first line therapy. However, the additional mechanisms of the TCA’s and MAOI’s may explain their use in treatment resistant anxiety.

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SSRI’s effect on the Locus Coeruleus is considered the most clinically significant anti-anxiety mechanism.