PTSD, and Serotonin
<p>Other studies indicate that people that suffer from PTSD have chronically low levels of <a title="Serotonin" href="/wiki/Serotonin">serotonin</a> which contributes to the commonly associated behavioral symptoms such as anxiety, ruminations, irritability, aggression, suicidality, and impulsivity.<sup id="cite_ref-Olszewski_2005_40_20-1" class="reference"><a href="#cite_note-Olszewski_2005_40-20">[19]</a></sup> </p>
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Serotonin also contributes to the stabilization of glucocorticoid production.</p>
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Serotonin taken orally as a pill is not able to easily cross the blood brain barrier, hence either tryptophan or 5-hydroxy-trytophan are good natural options since they convert into serotonin after going into the brain. </p>