If you have been prescribed Wellbutrin, it’s helpful to know how long it stays in your system for a number of reasons.
For one, if you are considering going off it for any reason—and you should always consult a doctor first before doing so—you need to know how long it stays in your system to accurately identify if you are experiencing adverse effects due to discontinuation.
Another reason you may be curious about how long Wellbutrin stays in your system is if you have an upcoming drug test.
Although Wellbutrin isn’t commonly abused, it’s still possible to misuse this drug, and its main active ingredient is also a common cause of false-positives for amphetamine drugs.
Here, we break down how Wellbutrin works, how long it stays in your system, and more.
It’s also important to know that it comes in two different formats, and each type stays in the body for a different amount of time, which we will also cover.
What is Wellbutrin?
Wellbutrin is a combination of the active ingredient bupropion delivered in the form of a hydrochloride salt, usually as a tablet.
There are two brand name forms of Wellbutrin; Wellbutrin SR (sustained release) and Wellbutrin XL (extended release).
These are known as “atypical antidepressants” and they work differently from most other types of antidepressants.
Both types of Wellbutrin are used to treat depression.
In addition, each type can be used to treat other conditions.
Formerly, bupropion was commonly prescribed for different types of mental illness including bipolar disorder, although it is not the first choice for such patients today.
While both types of Wellbutrin can be used to treat depression, Wellbutrin XL and SR are not interchangeable.
Wellbutrin XL can be prescribed for depression and for seasonal affective disorder (SAD), which is a specific type of depression that people typically experience during the fall and winter when there are fewer hours of sunlight.
Wellbutrin XL is taken once a day, and releases slowly so that the level of medication in the body remains stable instead of spiking and dipping.
It can take almost five hours for this medication to reach steady levels in the bloodstream, but it keeps releasing medication for up to 24 hours.
Wellbutrin SR can also be prescribed for depression, and is FDA-approved to help people quit smoking, as well.
It is generally taken twice a day, as it absorbs into the body a little more quickly than the XL version does.
It reaches steady levels more quickly—in about three hours— but only releases medication for up to 12 hours.
How Wellbutrin works
Bupropion is a norepinephrine-dopamine reuptake inhibitor drug (NDRI).
It binds with the norepinephrine transporter (NET) and dopamine transporter (DAT), inhibiting the reuptake of these neurotransmitters, which help in regulating mood, sleep, restlessness, memory retrieval, arousal, and pleasure.
Reuptake decreases levels of these neurotransmitters in the brain, resulting in depression and other depressive disorders like SAD.
By inhibiting reuptake, Wellbutrin helps reverse these effects.
The main difference between bupropion and selective serotonin reuptake inhibitors (SSRIs) is that serotonin reuptake is not inhibited with bupropion, meaning most people have fewer issues with arousal, although weight gain is still a common side effect.
How Long Does Wellbutrin Take to Work?
Bupropion has what is known as a slow-acting mechanism of action, which means it doesn’t work immediately.
It typically takes one or two weeks to start seeing changes in mood or a decrease in depression or urges to smoke, and a few more weeks after that to achieve full effects in your system.
A medication’s half-life is how long it takes for the amount of medication in the blood plasma to drop to 50% of original strength.
For Wellbutrin, the half-life varies depending on the formulation, but it can be up to 21 hours.
Factors That Influence How Long Wellbutrin Stays in Your System
The amount of time a drug stays in your system is related to how long it takes for your body to metabolize it.
Bupropion is mainly metabolized by your liver.
If your liver isn’t working well or not functioning at 100%, it can take a lot longer for it to process the medication out of your system.
It’s advised that you take regular blood tests to check your liver function to make sure you’re able to keep taking Wellbutrin safely.
Renal disease (kidney disease) can also affect how fast Wellbutrin clears your system.
So can factors like age, taking other medications, and drinking alcohol while taking Wellbutrin.
Alcohol also carries an increased risk of causing seizures if taken with bupropion.
How Long Does Wellbutrin Appear on A Drug Test?
If your main concern is about Wellbutrin showing up on a drug test, stop for a moment and think about why you’re concerned.
Wellbutrin can occasionally show up as a false positive for methamphetamine salts, but this is a common enough occurrence that showing your prescription will usually clear up any misunderstanding.
If you absolutely cannot fail a drug test, and are concerned enough about the idea to risk missing a few doses of your medication (which is not recommended by medical professionals), you need to understand how long the drug stays in different parts of the body.
Overall, it takes around four days for all bupropion to exit the body.
However, most of it clears specific parts of the body much faster.
For example, more than 60% is excreted in urine in the first 24 hours.
So, if you show up for a drug test before taking the next dose of XL (or skip only one dose of SR), it would be unlikely to cause a result.
Wellbutrin can stay in the blood longer than four days, but blood tests don’t typically look for the compound it would show up as.
In hair, it can stay up to 90 days.
But again, it’s not commonly something that’s being looked for.
The main concern is usually the possibility of it showing up in a urine test.
In fact, more than 40% of false positive methamphetamine test results in one study were directly linked to people using bupropion therapeutically.
If you’re being tested for methamphetamine use with a urine sample, take your proof of prescription with you and let the testing facility and your employer know up front that you are on a medication known to cause a false positive.
Symptoms of Wellbutrin Withdrawal
So, why not just stop taking Wellbutrin in the days or weeks leading up to a scheduled drug test?
The withdrawal symptoms for stopping an antidepressant suddenly can be debilitating.
There is a reason your doctor likely started you out on a low dose and may have gradually increased it from there over a period of a few weeks.
This is called titration, and it keeps the sudden introduction or removal of a drug from your system from shocking your body.
Removing Wellbutrin from your system should be the same process in reverse; slowly tapering the dose until the amount of medication in your blood decreases to a safe level to stop the medication.
As with the original upward titration, this is a process that takes weeks—not days.
For many, symptoms of Wellbutrin withdrawal aren’t just a return of depression or the desire to take up smoking again.
You can also experience symptoms you didn’t have before due to your brain’s new reliance on the drug.
Without Wellbutrin making changes to the level of dopamine in your brain and delivering a stimulant-like effect, you may start to crave the balance it gave you.
Stopping Wellbutrin abruptly can cause irritability, sleeplessness, anxiety, headaches, and general aches and pain.
You might try to replace Wellbutrin with other substances such as alcohol in search of that good feeling.
To avoid doing this make sure to be kind to yourself and make room for self-care during this time.
If your doctor recommends you stop Wellbutrin, they will discuss your options and help you taper off of the medication slowly and safely.
This generally leads to fewer side effects, but you may still have some withdrawal symptoms, especially if you have been on the drug for a long time.
Tips for Coping with Wellbutrin Withdrawal
Many people have symptoms from discontinuing antidepressants that mimic the symptoms of a bad flu, known as antidepressant discontinuation syndrome.
Bupropion is no different in that regard from any other antidepressants. Here are some tips for coping with withdrawal from Wellbutrin:
People who turn to psychotherapy while they are going through the process of discontinuing an antidepressant are less likely to have a relapse or suffer unbearable symptoms that drive them to try and find a replacement for the drug.
Sadly, fewer than 20% of people on antidepressants get psychotherapy, even though it is highly effective for treating depression as well as overall mental health.
Keep in communication with your healthcare provider
Following your doctor’s advice for tapering down your medication and communicating any new symptoms or concerns can help you stay the course and successfully discontinue the drug.
Your doctor is there to help you be safe and succeed.
If you are having serious side effects, they can recommend treatments or medication to help dampen the withdrawal symptoms until your body stabilizes.
Eat right and exercise
Making sure you build your daily schedule around breaks for food and activity can help.
Plan out meals and look for exercise options that put you outdoors in the sunlight and fresh air.
Taking care of your body while it works to stabilize you can help minimize the effects of tapering down your Wellbutrin.
When to See a Healthcare Professional
If you are currently taking Wellbutrin, it’s important to follow your doctor’s prescription instructions and consult them first before making any changes to dosage.
If you miss a dose, reach out for medical advice on what to do, though it’s generally advised not to take two doses all at once to make up for a missed dose.
If you are experiencing mental or physical side effects with Wellbutrin, make sure to communicate those symptoms with your doctor.
If your symptoms are severe, don’t stop taking Wellbutrin until you’ve checked with your doctor first.
Quitting Wellbutrin cold turkey can worsen side effects in some cases.
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Frequently Asked Questions
K Health articles are all written and reviewed by MDs, PhDs, NPs, or PharmDs and are for informational purposes only. This information does not constitute and should not be relied on for professional medical advice. Always talk to your doctor about the risks and benefits of any treatment.
K Health has strict sourcing guidelines and relies on peer-reviewed studies, academic research institutions, and medical associations. We avoid using tertiary references.
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Frequency of false positive amphetamine screens due to bupropion using the Syva EMIT II immunoassay. (2011.)
Bupropion-Associated Withdrawal Symptoms: A Case Report. (1999.)
Going off antidepressants. (2020.)
Antidepressant Discontinuation Syndrome. (2006.)