Pharmacokinetics of thiamin after oral administration of thiamin tetrahydrofurfuryl disulfide to humans.

We performed a pharmacokinetic analysis of the blood thiamin profile after oral administration of thiamin tetrahydrofurfuryl disulfide (TTFD) to healthy adults. To distinguish between thiamin derived from TTFD ingestion and that from previous dietary intake, the baseline thiamin level was subtracted from the apparent blood vitamin levels measured after administration. Following administration of 100 mg of TTFD, the peak blood thiamin level was almost 10 times the baseline level and the blood thiamin profile could be simulated by a two-compartment model to obtain reasonable pharmacokinetic parameters. When the blood thiamin profile for a 10-mg dose of TTFD was estimated using scaled-down pharmacokinetic parameters derived at the 100-mg dose level, a reasonable fit for the raw data obtained at 10-mg dose was obtained. Therefore, the parameters derived from the data at a dose of 100 mg appeared to be reliable. Since even 180 mg of TTFD is completely absorbed and the absorption ratio is independent of the dose, it can be concluded that gastrointestinal absorption of TTFD is good within the dose range.