Are Monoamine oxidase inhibitors (MAOIs) as dangerous as they are made out to be? I am new to pharmacology, but here is my understanding of MAOIs and antidepressants in general:
There is a presynaptic neuron that stores serotonin in vesicles. The serotonin is made by tryptophan.
Release of serotonin from the presynaptic neuron stimulates various 5-hydroxytryptamine (5-HT) receptors in the postsynaptic neuron. The serotonin goes back to the presynaptic neuron via the serotonin transporter (SERT or 5-HTT) transporter. Most of this serotonin is repackaged into various vesicles while some of the other serotonin is broken down by MAO enzyme.
Selective Serotonin Reuptake Inhibitors (SSRIs) inhibit the SERT transporter to various degrees depending on which one it is. This increases the availability of serotonin to bind to various postsynaptic 5-HT receptors.
Serotonin-Norepinephrine Reuptake Inhibitors (SNRIs) inhibit both the SERTs and norepinephrine transporters (NETs) to varying degrees depending on the medication which increases availability of both serotonin and norepinephrine to bind to various postsynaptic 5-HT receptors and beta and alpha-1 receptors.
MAOIs don't inhibit SERT, NET or dopamine transporter (DAT) but they inhibit the MAO enzymes. So serotonin and norepinephrine travel back to presynaptic neurons and are stored in various vesicles. They are not broken down by the MAO enzymes.
Now it seems that if you inhibit the MAO enzymes, there is more tyramine which leads to an increase in catecholamines. This could cause a stroke.
Are there any agents that decrease tyramine in the first place? Wouldn't this make a person not have to follow a restrictive diet?