The Collaborative International Dictionary of English v.0.48:

Tannigen \Tan"ni*gen\, n. [Tannin + -gen.] (Pharm.)
   A compound obtained as a yellowish gray powder by the action
   of acetyl chloride or acetic anhydride or ordinary tannic
   acid. It is used as an intestinal astringent, and locally in
   rhinitis and pharyngitis.
   [Webster 1913 Suppl.]