Gamma-hydroxybutyrate (GHB), a GHB-/GABAB-receptor agonist, produces euphoric, disinhibiting, and vitality-enhancing effects in healthy men. In a randomized, placebo-controlled crossover trial with 16 males, a single 20 mg/kg dose increased charitable donations and prosocial money distributions among participants who initially showed low prosociality. However, GHB did not alter emotion recognition, empathy, theory-of-mind, or basic cognitive functions. The drug raised plasma progesterone levels but left oxytocin, testosterone, cortisol, aldosterone, DHEA, and ACTH unchanged. These findings suggest that GHB's mood and prosocial effects may involve GHB-/GABAB-receptors and progesterone rather than typical social hormones like oxytocin or testosterone.
Antidepressants consistently reduce how often people recall their dreams, especially tricyclic antidepressants and phenelzine, with a less consistent effect for SSRIs and SNRIs. Tricyclic antidepressants also make dream content more positive, while withdrawing from them or from MAO inhibitors can cause nightmares. In contrast, taking or withdrawing from SSRIs/SNRIs tends to intensify dreaming, which may sometimes lead to nightmares. These findings come from a systematic review of 21 clinical studies and 25 case reports covering 1950 to 2010, involving both depressed patients and healthy volunteers. The authors note that despite clear pharmacological effects, research on this topic has been scarce over the past 60 years.