Thymosin β4 has been tested in multicenter trials sponsored jointly by RegeneRx Biopharmaceuticals Inc (Rockville, MD, USA) and Sigma Tau (Pomezia, Italy) in the United States and Europe in patients with bed sores, ulcers caused by venostasis, and Epidermolysis bullosa simplex and was found to accelerate bed sore and stasis ulcer repair by one month. It has also been tested in patients with chronic neurotrophic corneal epithelial defects and found to promote repair.
Both the production of oxytocin and response to oxytocin are modulated by circulating levels of sex steroids. The burst of oxytocin released at birth seems to be triggered in part by cervical and vaginal stimulation by the fetus, but also because of abruptly declining concentrations of progesterone. Another well-studied effect of steroid hormones is the marked increase in synthesis of uterine (myometrial) oxytocin receptors late in gestation, resulting from increasing concentrations of circulating estrogen.
Thymosin β4 (TMSB4X, Tβ4) is the most abundant G-actin binding peptide of the cytosol and is a potent proangiogenic factor. The role of myocardin-related transcription factors (MRTF) and serum response factor (SRF) for this function was examined in experimentally induced prolonged ischemic myocardium areas of transgenic pigs ubiquitously and constitutively overexpressing Tβ4 driven by the cytomegalovirus promoter. Upon induction of a reversible loss of cardiomyocyte function which is amenable to therapeutic neovascularization, transgenic pigs did not experience a significant loss of perfusion nor myocardial function at rest or under rapid pacing. Functional vascular regeneration by induced capillary growth and maturation was found in the transgenic pigs (Hinkel et al., 2014).
Studies demonstrate that TB-500 is a potent, naturally occurring wound repair factor with anti-inflammatory properties. Tß4 is different from other repair factors, such as growth factors, in that it promotes endothelial and keratinocyte migration. It also does not bind to the extracellular matrix and has a very low molecular weight meaning it can travel relatively long distances through tissues. One of TB-500 key mechanisms of action is its ability to regulate the cell-building protein, Actin, a vital component of cell structure and movement. Of the thousands of proteins present in cells, actin represents up to 10% of the total proteins which therefore plays a major role in the genetic makeup of the cell.
Dietary supplements containing 5-HTP are claimed to help promote feelings of happiness and general well-being as well as a wide range of other positives such as appetite control, reduced anxiety, and improved mood, sleep and feelings of relaxation. However, there is no conclusive evidence showing that it is effective, and there is no clear "therapeutic" dose of 5-HTP.

The reality is that people are always going to self-medicate. Boots, Amazon and H&B all sell 5-HTP, and in theory you could keep buying it and taking it for as long as you like. But it's important to know the facts. It shouldn't be used in conjunction with an SSRI, for example. In that situation, if the body is preventing serotonin breakdown while also getting extra serotonin, which leads to seriously unhealthy levels of serotonin activity.
Potential side effects of 5-HTP include heartburn, stomach pain, nausea, vomiting, diarrhea, drowsiness, sexual problems, vivid dreams or nightmares, and muscle problems.[19] Because 5-HTP has not been thoroughly studied in a clinical setting, possible side effects and interactions with other drugs are not well known. According to the US National Institute of Health TOXNET, 5-HTP has not been associated with serotonin syndrome or any serious adverse events in humans.[20] Across multiple studies, 5-HTP also been reported to not cause any noticeable hematological or cardiovascular changes.[21] 5-HTP also has not been associated with eosinophilia.[22]