By Irfana Parveen

B.Sc (Psychiatry Ward)

25 April 2022
Medically reviewed by
Sumayya Salam
Pharm D
How long does venlafaxine stay in your system
Table of Contents

Venlafaxine, sold under the brand Effexor, is an antidepressant medication used to treat medical conditions such as major depressive disorder, anxiety, and panic disorder. 

Venlafaxine is not available over the counter. Buy Venlafaxine online from a certified online pharmacy, but it is important to consult your health care before consuming this medication.

It is categorized under the group of drugs called selective serotonin and norepinephrine reuptake inhibitors (SSNRIs).

Venlafaxine is available in two formulations, namely

Bluffed by Others? Count on us

Venlafaxine (Effexor XR)



Trackable Delivery within 2 weeks


Certified Pharmacy

How long does venlafaxine stay in your system?

Venlafaxine comes in two forms: immediate-release pills and extended-release tablets. The drug's half-life varies based on the drug's formulation. 

The half-life of immediate-release pills is roughly 5 hours, whereas extended-release tablets have an 11-hour half-life.

It takes around a day for the medicine to be eliminated on average. It may take around 16.5 hours, while some patients may take a day and a half to eliminate the medicine.

  • Venlafaxine may be detected in a drug test 48 hours after taking it.
  • Venlafaxine stays in your blood for three days and can be detected in a blood test.
  • Antidepressants are detectable in hair follicles for at least 16 months. Venlafaxine can be discovered in your hair or 1.5 years roughly.

Study on antidepressant half-life and its association with suicide ideation in children and adolescents:

Aim: the purpose of the study was to determine the association of general property of antidepressants such as dosage half-life to the risk of suicidal ideation and behavior.

Method: The FDA's original and published versions of their pediatric antidepressant meta-analysis yielded relative risks for suicide behaviour (ideation, attempt, or preparation) for seven antidepressants. The correlation between suicidal behaviour and antidepressant half-life was examined.

Findings: The initial analysis revealed a substantial association as previously reported by Weiss and Gorman. When results from the Treatment of Adolescent Depression Study (TADS) were added in the published meta-analysis, the correlation was robust to a change in the suicidality rating for the longest half-life medication, fluoxetine.

Conclusion: According to a recent FDA meta-analysis, the risk of suicide ideation or behaviour in short-term antidepressant studies including children or adolescents appears to be at least partly associated with antidepressant half-life. (Angelo, L.J. and Lee, K.C., 2013)

Are There Any Factors Influencing Venlafaxine's Stay?

The length of time it takes for venlafaxine to leave your body depends on a number of factors, including:

  • Age

The time it takes for venlafaxine to be eliminated can be affected by age. The medicine takes longer to be eliminated in elderly patients with poor blood flow and kidney function. Venlafaxine's half-life is shortened by 24% in older adults when compared to younger people.

  • Genetic

Venlafaxine's ability to persist in the body is also influenced by genetics. When a person's pharmaceutical metabolism is poor, it takes longer for the drug to be eliminated, and vice versa.

  • How much to take.

The duration of the medicine is also determined by the dosage. Patients on lower dosage metabolize and eliminate the medication more quickly.

  • Additional substances

Venlafaxine's duration of action can be affected by taking it with other medications. Depending on the substances consumed, it may lower or raise the drug content in your blood. Mixing medications, on the other hand, can result in major negative effects, therefore it's not a good idea.

  • The state of the liver

Venlafaxine's elimination half-life is similarly influenced by liver function. Patients with hepatic fibrosis or cirrhosis are more likely to keep the medication in their bodies than those with normal hepatic functioning.


  • Venlafaxine is an SSRI antidepressant drug used to treat major depression, anxiety and panic disorders.
  • Venlafaxine half-life depends on its formulation
  • Venlafaxine half-life for immediate release tablets is 5 hours whereas for extended release tablets it is around 11 hours
  • It takes around a day and a half for the drug to be completely eliminated from your body
  • Factors such as age, mixing with other drugs, genetics etc. also influence the stay of the drug.
What's on your mind?

Start a conversation, Post with kindness.