Melanotans include melanotan I (afamelanotide) and melanotan II. Both melanotan I and II are widely abused to obtain a cosmetic tan. The melanotans are potent, non-selective melanocortin receptor agonists affecting MC1, MC3, MC4 and MC5 receptors. These receptors are responsible for many physiological systems including: pigmentation, energy, sexual function, immune system, inflammation and the cardiovascular system.
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
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.