Prosultiamine is a synthetic derivative of thiamine (Vitamin B1) developed to improve oral absorption and tissue penetration compared to standard thiamine. Its primary justification for use in peripheral neuropathy is supported by scientific literature, particularly in the context of neuropathy associated with thiamine deficiency, such as in beriberi and some diabetic neuropathies.

Multiple small-scale clinical studies, particularly from Japan and other Asian countries, have investigated prosultiamine and related fat-soluble thiamine derivatives (such as benfotiamine) for diabetic and other forms of peripheral neuropathy. These studies generally demonstrate improvement in neuropathic symptoms, nerve conduction velocity, and patient-reported outcomes after supplementation, although the sample sizes are small and study designs often lack rigorous blinding and randomization.

The putative mechanism involves the correction of subclinical or overt thiamine deficiency in nerve tissues, reduction of advanced glycation end-products, and improved energy metabolism within neurons. Guidelines in some countries reference thiamine or its derivatives as part of a comprehensive approach to diabetic neuropathy, but Western clinical guidelines do not routinely recommend prosultiamine specifically, citing insufficient large-scale, high-quality trials.

In summary, there is moderate scientific evidence, mainly from small trials and mechanistic studies, for the use of prosultiamine in peripheral neuropathy, particularly in individuals with or at risk for thiamine deficiency. However, more robust clinical trials are needed to firmly establish efficacy and inform routine clinical use.