It sounds like there is no evidence at all for parasites.
This sound psychological.
That said, such sensations can indicate systemic illness.
Liver or kidney problems.
Internal parasites which possibility is alleviated with stool samples.
Heavy metal toxicity.
Psychological problems and anxiety.
Alcohol and other toxins.
B vitamin deficiency.
If this is all ruled out, and dermatology
finds nothing, psychiatry is indicated.
OK, so that is an initial answer….
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