The story
Probably from venla- (of unknown origin) + ph(enyl) + -ax- (“alteration of (cycloh)exa(ne)”) + (am)ine.
Etymology from Wiktionary, CC BY-SA 4.0.
venlafaxine
Today it means: A drug that functions as an SNRI and is used in the form of its hydrochloride C₁₇H₂₇NO₂·HCl especially to treat depression, anxiety, and panic disorder. It is marketed under the trademark Effexor. Full definition →