Peripheral neuropathies.

The present chapter is an overview of peripheral neuropathies for which placebo and nocebo responses and/or placebo and nocebo effects have been investigated to date. Even if most of our knowledge in this field comes from pain studies, a rapidly expanding picture emerges from the original research works conducted over the past 7 years on: painful diabetic neuropathy, postherpetic neuralgia, neuropathic complications of thoracotomy, carpal tunnel syndrome, Guillain-Barré syndrome, and chronic inflammatory demyelinating polyneuropathy (CIPD). Otherwise, very little, if anything, is known for the other peripheral neuropathies. Significant placebo effects were reported for neuropathic complications of thoracotomy and CIPD. Treatment expectations emerged as predictors of treatment outcome in neuropathic complications of thoracotomy. Finally, special attention to contextual factors, inclusion of no treatment arms, and control for baseline covariates should be given to further improve research in clinical trials of peripheral neuropathy.