An internal foot itch indicates an internal disease such as diabetes or a condition such as psoriasis or scabies, states WebMD. Some neurological illnesses that lead to neuropathic pain cause internal itch instead, according to PubMed Central.
Determining neuropathy in the feet involves a physical exam that tests for sensory nerve damage and muscle strength, according to Foot Vitals. Blood tests to check for diabetes and other systemic diseases also aid in diagnosis, as do nerve biopsies. Assessment of symptoms accompanying internal foot itches aid in precise diagnosis and creating an effective treatment plan such as prescription medications, creams, corticosteroids and topical ointments, states WebMD.