A brand name version of bupropion, Wellbutrin is half out of your system within 21 hours and 99% gone within 4.4 days.

Most drug tests don’t screen for Wellbutrin because it is an antidepressant that does not have recreational uses. But if you overdose on another substance, medical professionals may run a toxicology screen that looks for this drug and any others in your system.

To work, Wellbutrin needs to build up in your system, and that process takes weeks. Keep reading to get an idea of how long Wellbutrin stays in your urine, hair, blood, and saliva.

How Long Does Wellbutrin Stay in Your Urine?

Again, most drug tests do not look for antidepressants, but Wellbutrin can lead to a false-positive for amphetamines in urine screening. Wellbutrin can be detected in urine for up to 3 days.

In fact, Wellbutrin is the most common reason people get false-positive amphetamine results. The test that generates these false-positive results is called the “EMIT II immunoassay” and over 40% of drug testing labs use this test. If you are on Wellbutrin, let the doctor know so they can use a more specific test.

How Long Does Wellbutrin Stay in Your Hair?

Again, there is not much research on how long Wellbutrin stays in your hair, but all drugs tend to be detectable in hair tests for relatively long periods of time. Standard hair follicle tests can detect up to 90 days after the drug was last taken.

How Long Does Wellbutrin Stay in Your Blood?

After the last time taken, Wellbutrin is detectable in blood tests for about 4.4 days. This number is based on the half-life of the drug which refers to the amount of time it takes for half the dosage to leave your system.

On average the half-life of Wellbutrin is 21 hours, but that can vary by about 9 hours in either direction depending on personal factors including the following:

  • Age
  • Weight
  • Genetics
  • Metabolism
  • Dosage
  • Duration of time taken
  • Frequency of use
  • Health condition
  • Other drugs in your system

For example, if you take a small dose and have a high metabolism, you may be able to clear half a dose from your system in just 12 hours. That’s the average half-life minus nine hours. 

In contrast, if your liver doesn’t work well, your body takes longer to clear drugs out of your system. For people with a poor functioning liver, Wellbutrin has a half-life of 32 hours plus or minus 14 hours. In other words, people with liver failure can take up to 46 hours to clear half a dose from their systems. 

How Long Does Wellbutrin Stay in Your Saliva?

In drug tests, saliva levels tend to correlate with blood levels. Based on that fact, you can expect Wellbutrin to be detectable in saliva for about 4.4 days.

The presence of drugs in your saliva varies based on how you ingest the drug. Since most Wellbutrin is taken orally, it should appear in your saliva, but if you get an injection, the results will be different.

How Long Does Wellbutrin Stay in Lab Tests?

As indicated above, the results of a lab test vary depending on how long you’ve been taking Wellbutrin, personal health factors such as liver functioning, other drugs in your system, and the type of screening. On average, you can expect to test positive for Wellbutrin for the following amounts of time:

  • Urine: Up to 3 days
  • Hair: 90 days
  • Blood: 4.4 days average
  • Saliva: Estimated 4.4 days

These results are not the same for everyone. After you take Wellbutrin or other antidepressants, how long it lasts in your system depends on a range of personal factors and the amount of the dosage. But in all cases, the brain effects of this drug fade while the drug is still detectable in your system.

To be effective, this drug has to build up in your system. You usually won’t feel any effects if you just take a single dose. On the flip side, this drug also takes a while to leave your system, and quitting cold turkey can be dangerous.

To protect yourself, you need to taper your usage over one to two weeks as the drug slowly leaves your system, and you must consult with a healthcare provider during this process.

If you want to quit Wellbutrin or if you’re struggling with addiction to other drugs and alcohol, there are options. Call your local treatment center to learn how to get help in your area.


  1. https://www.health.harvard.edu/diseases-and-conditions/going-off-antidepressants
  2. https://www.rxlist.com/wellbutrin-drug.htm#interactions
  3. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3724447/
  4. https://www.rxlist.com/wellbutrin-drug.htm
  5. https://www.ncbi.nlm.nih.gov/books/NBK64092/
  6. https://www.verywellmind.com/wellbutrin-withdrawal-symptoms-timeline-treatment-4176725
  7. https://www.aafp.org/afp/2010/0301/p635.html

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