Makes sense seeing a lot of people on here that seem to have been chasing their tails forever with constant negative tests and no improvement. I see a lot of people even describe feeling crawling sensations. I don't think all who don't really have parasites are suffering from a psychological condition. I think a lot have been misdiagnosed with other physical conditions like liver disease which is becoming epidemic.
Delusional parasitosis, also known as Ekbom's syndrome, is a form of psychosis whose victims acquire a strong delusional belief that they are infested with parasites, whereas in reality no such parasites are present. Very often the imaginary parasites are reported as being "bugs" or insects crawling on or under the skin; in these cases the experience of the sensation known as formication may provide the basis for this belief.