Normally, a primary care provider has the knowledge to help with the behavioral adjustments that will treat lichen simplex. If not, dermatology might help. Ultimately, the treatment is up to you, not an outside expert.
Dermatologist treats that condition
The Dermatologist (skin doctor)
Foot doctor
I think its an orthapeadic doctor
an oncologist
A psychologist.
gastroenteroligist
nuerologist
A gastroenterologist treats stomach pain.
A GP should do.
Pediatrician.
podiatrist