Peganum Harmala contains Harmaline, which is a strong MAO-inhibitor, and it is therefore often used as a 1st component in Ayahuasca ceremonies in order to inhibit the metabolisation of an orally-administered DMT molecule (2nd component).
In this view, if MAOI is neither present in the plant nor added to the mixture, the enzyme MAO will break apart DMT in the human gut, preventing the active molecule from entering blood and brain.
Trazodone appears to be relatively safer than TCAs, MAOIs, and a few of the other second-generation antidepressants in overdose situations, especially when it is the only agent taken.