GAL and postural orthostatic tachycardia syndrome: Existing literature is inconclusive regarding the role of galanin in orthostatic intolerance: researchers have reported increased galanin levels at the point of presyncope and a high galanin level association with orthostatic intolerance (Hinghofer-Szalkay et al., 2011; O’shea et al., 2015) while others have reported that in patients with HUT-induced syncope galanin does not change either preceding – or during – loss of consciousness (Bondanelli et al., 2003).