Missing a dose of my effexor (venlafaxine) er, even by a few hours, makes my face feel like it's dropping on a roller coaster, and me dizzy. i'm on 300mgs. help!

Rare known reaction: Discontinuation of Effexor (venlafaxine) can result in severe withdrawal symptoms. Just missing one dose may trigger dysphoria (a state of anxiety, depression, or unease), tremor, nausea, headache, hallucinations, paresthesia (a sensation of pricking, tingling, or creeping on the skin), impaired concentration, fatigue, dizziness, and vertigo.