How Long Does Effexor Stay in Your System?

Written by Austin Campion

10 October, 2009

Venlafaxine

Effexor (or Efexor) is a brand name for the drug venlafaxine. In 2007 it was the most commonly prescribed SNRI (serotonin-norepinephrine reuptake inhibitors). Used primarily for the treatment of major depressive disorder, venlafaxine leaves the body quite quickly. It is processed thoroughly and quickly by the liver and excreted in the urine. There are also extended release versions of Effexor containing the same drug, but elimination from the body will be somewhat slower as the drug is released more slowly during digestion.

Is This an Emergency?

If you are experiencing serious medical symptoms, seek emergency treatment immediately.

Elimination From the Body

In standard venlafaxine the elimination half-life is 3-13 hours for both pill and liquid forms. This means that the effects of venlafaxine will fade within a day, and possibly much faster. The drug will no longer be detectable in the body within 5-7 days.

Missed Doses and SSRI Discontinuation Syndrome

Symptoms When Stopping Lexapro

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Venlafaxine is not as forgiving of skipped doses as many reuptake inhibitors. Recurrence of symptoms can occur when even a single dose is missed. In a study at Massachusetts General Hospital it was found that a significant number of patients taken off venlafaxine experienced symptoms of SSRI discontinuation syndrome for three days after they stopped taking the drug. Consequently, though venlafaxine is not associated with addiction, most doctors will prefer to taper off the dose so as to avoid this syndrome.