Fursultiamine (INN; chemical name thiamine tetrahydrofurfuryl disulfide or TTFD; brand names Adventan, Alinamin-F, Benlipoid, Bevitol Lipophil, Judolor, Lipothiamine) is a medication and vitamin used to treat thiamine deficiency.

Chemically, it is a disulfide derivative of thiamine and is similar in structure to allithiamine.

[1] It was synthesized in Japan in the 1960s from allithiamine for the purpose of developing forms of thiamine with improved lipophilicity for treating vitamin B1 deficiency (i.e., beriberi),[1] It was subsequently commercialized not only in Japan but also in Spain, Austria, Germany, and the United States.

[2]