Half the group of burned volunteers got a whiff of Eau de Oxytocin, half got a sniff of Eau de Placebo. Those who sniffed the oxytocin were more trusting and ready to invest with an anonymous trustee a second time than were the placebo-exposed subjects. And when they were asked “Do you want to try this again?” the oxytocin-treated volunteers responded more quickly than the volunteers who hadn’t gotten the nose full of Trust Spray.6
An estimated 1.4 million people sustain traumatic brain injury (TBI) each year in the United States, and more than 5 million people are coping with disabilities from TBI at an annual cost of more than $56 billion.1 There are no commercially-available pharmacological treatment options available for TBI because all clinical trial strategies have failed.2,3 The disappointing clinical trial results may be due to variability in treatment approaches and heterogeneity of the population of TBI patients.4-9 Another important aspect is that most clinical trial strategies have used drugs that target a single pathophysiological mechanism, although many mechanisms are involved in secondary injury after TBI.4 Neuroprotection approaches have historically been dominated by targeting neuron-based injury mechanisms as the primary or even exclusive focus of the neuroprotective strategy.3 In the vast majority of preclinical studies, the treatment compounds are administered early and, frequently, even before TBI.10,11 Clinically, the administration of a compound early may be problematic because of the difficulty in obtaining informed consent.12
The relationship between oxytocin and human sexual response is unclear. At least two non-controlled studies have found increases in plasma oxytocin at orgasm in both men and women. The authors of one of these studies speculated that oxytocin's effects on muscle contractibility may facilitate sperm and egg transport. Murphy et al. (1987), studying men, found that oxytocin levels were raised throughout sexual arousal and there was no acute increase at orgasm.  A more recent study of men found an increase in plasma oxytocin immediantly after orgasm, but only in a portion of their sample that did not reach statistical significance. The authors noted that these changes "may simply reflect contractile properties on reproductive tissue."
Romantic attachment: In some studies, high levels of plasma oxytocin have been correlated with romantic attachment. For example, if a couple is separated for a long period of time, anxiety can increase due to the lack of physical affection. Oxytocin may aid romantically attached couples by decreasing their feelings of anxiety when they are separated.
Cells were pretreated with indicated concentrations of Tβ4 peptide for 2 hours, post-incubated with 200 μM H2O2 for 48 hours, and then conditioned medium (CM) was collected. Mouse BMMs were cultured with CM in the presence of M-CSF (30 ng/mL) and RANKL (100 ng/mL), as described in Materials and methods. After 5 days, cells were fixed and stained for TRAP as a marker of osteoclasts (A), and the number of TRAP-positive multinucleated cells (MNCs) was scored (B). TRAP osteoclast activity was assayed using the TRAP cytochemical stain technique (C). * Statistically significant differences compared with the control, p<0.05. The data presented were representative of three independent experiments.
5-HTP can affect a brain chemical called serotonin. Dextromethorphan (Robitussin DM, others) can also affect serotonin. Taking 5-HTP along with dextromethorphan (Robitussin DM, others) might cause too much serotonin in the brain and serious side effects including heart problems, shivering, and anxiety. Do not take 5-HTP if you are taking dextromethorphan (Robitussin DM, and others).
A 2002 review concluded that although the data evaluated suggests that 5-HTP is more effective than placebo in the treatment of depression, the evidence was insufficient to be conclusive due to a lack of clinical data meeting the rigorous standards of today. More and larger studies using current methodologies are needed to determine if 5-HTP is truly effective in treating depression. In small controlled trials 5-HTP has also been reported to augment the antidepressant efficacy of the antidepressant clomipramine.