5-Hydroxy Tryptophan is an amino acid which is the direct precursor (by decarboxylation) to 5-Hydroxy Tryptamine, commonly called Serotonin. Serotonin was first discovered in blood platelets, which release it in response to injury. It constricts blood vessels (hence it's name, sero-tonin), promotes formation of clots, and induces inflammation, similar to the related chemical histamine. It suppresses mitochondrial respiration, promoting inefficient glycolysis and inhibiting energy production. In neurons, it synergizes with glutamate and causes the influx of calcium and a decrease in ATP levels, which may promote cell death. It has been implicated in the fatigue caused by intense exercise, which can be prevented using branch-chain amino acids, which compete with serotonin for entry to cells. Serotonin is high in autism, alzheimer's, multiple sclerosis, schizophrenia, and other neurological dysfunctions. Some drugs that inhibit platelet serotonin uptake are presently sold as 'antidepressants', the implication being that low serotonin levels cause depression, or that serotonin corresponds to happiness. This is disingenuous. Several studies have actually correlated elevated serum serotonin levels with depression. Serotonin, released during stress, causes damage to the hippocampus and inhibits memory formation (and cognition in general). The popular theory of serotonin's behavioral effects is that it constricts the range of an organism's responses to stimuli, similar to its effects on blood vessels. On the other hand, drugs that replace or inhibit serotonin, such as LSD and MDMA, can prevent fatigue and vastly expand the range of behavior. I believe that serotonin has the opposite effects than those that are typically ascribed to it, and 5-HTP supplementation is unnecessary and probably deleterious in most cases.
TL : DR > It's dangerous.
