Pharmacokinetics of the transdermal delivery of benfotiamine

Accumulation of advanced glycation endpoints is a trigger to the development of diabetic peripheral neuropathy, which is a common complication of diabetes. Oral administration of benfotiamine (BFT) has shown some preclinical and clinical promise as a treatment for diabetic peripheral neuropathy. The purpose of this study was to evaluate the method of transdermal delivery of BFT as a possible, viable route of administration for the treatment of diabetic peripheral neuropathy. A single application of 10 mg of BFT was given to guinea pigs topically. The levels of thiamine (T), thiamine monophosphate, thiamine diphosphate, S-benzoylthiamine and BFT were measured in the blood, skin and muscle at different time points within 24 h. At the 24-h time point, following the single BFT dose, the T level was increased 10x in the blood, more than 7x in the skin and almost 4x in the muscle compared to the untreated animals. The total T content (total) was increased 7x in the blood, 17x in the skin and 3x in the muscle compared to the untreated animals. This strong increase in the tissue levels of T and the associated metabolic derivatives levels found in the blood and local tissues following a single dose indicate that topically applied BFT may be a viable and advantageous delivery method for the treatment of diabetic peripheral neuropathy.