How long to feel the effects of wellbutrin?

Wellbutrin is a brand-name drug that contains bupropion hydrochloride as the active ingredient. You may have known of Wellbutrin for its use in treating depression. However, besides depression, Wellbutrin is also used for other mental health conditions discussed below; and interestingly, different formulations of Wellbutrin are used for different indications. Please continue reading to learn about the uses and side effects of Wellbutrin.

Wellbutrin (bupropion) belongs to a group of antidepressants called norepinephrine-dopamine reuptake inhibitors (NDRIs), one of the atypical antidepressants. The exact mechanism of Wellbutrin is unknown; however, it is believed that Wellbutrin works by inhibiting the neurons (brain cells) from reabsorbing norepinephrine and dopamine after they have been released into the brain. These two neurotransmitters, norepinephrine and dopamine, are natural brain chemicals that help regulate mood, motivation, and certain brain responses affecting other body functions. Over time, Wellbutrin builds up a steady level of these neurotransmitters in the body which help reduce symptoms of a depressed mood while promoting the general sense of well-being.

One key thing to keep in mind is that the increase in levels of these brain chemicals does not occur overnight. This is why all antidepressants take about 6 to 8 weeks to show improvement in mood and motivation. However, it doesn’t mean you will have to wait that long to find out if this is the right medication for you. The first sign that Wellbutrin is working would take place between the first and second week when you would notice an improvement in appetite and sleep. You should let your provider know how you feel by week 4, including any improvement in mood or any side effects that do not get better over time.

Wellbutrin is available in different formulations, including immediate-release (IR), sustained-release (SR), and extended-release (XL) oral tablets. All Wellbutrin formulations contain bupropion; however, they are not interchangeable as each formulation is approved for different uses. These brand-name drugs are also available as low-cost generics.

The generic Wellbutrin is available in all 3 formulations, immediate-release (IR), sustained-release (SR), and extended-release (XL) oral tablets. Whereas the brand name Wellbutrin is only available as a sustained-release (SR) and extended-release (XL). Zyban is another brand name for Wellbutrin that was used for smoking cessation; however, Zyban has been discontinued in the U.S.

Compared to Wellbutrin XL, Wellbutrin SR is absorbed a bit faster and takes approximately 3 hours to reach a steady-state level in your body, whereas Wellbutrin XL can take up to 5 hours. Another difference between these two formulations is that Wellbutrin SR is dosed twice daily, while Wellbutrin XL only requires once daily dosing. This is a huge advantage for people who have trouble remembering to take their medications.

Wellbutrin SR is used to treat depression and help quit smoking. The SR form is available as 100 mg, 150 mg, and 200 mg oral tablets and is usually taken twice daily. For depression, the usual dose is 150 mg once daily in the morning;  after 3 days, based on tolerability, the dose can be increased to 150 mg twice daily at least 8 hours apart. The maximum daily dose is 400 mg. For smoking cessation, the dosing regimen is the same as for treating depression; however, the length of therapy is about 7-12 weeks, starting 1 to 2 weeks before the quit date.

Wellbutrin XL is released more slowly into the body for up to 24 hours; that’s why this medication only needs to be taken once a day. It is used to treat major depressive disorder and seasonal affective disorder, a type of depression that usually occurs in the fall and winter months when the days are shorter with less daylight. Wellbutrin XL is available as 150 mg and 300 mg tablets and, as mentioned, is taken once a day. Your doctor may start you on a dose of 150 mg once daily in the morning and may increase it to 300 mg once daily after 4 days.

Wellbutrin is not approved by the Food and Drug Administration (FDA) to treat bipolar disorder. Prescribers may use Wellbutrin to treat bipolar disorder as an off-label use for this mental health condition. Keep in mind that Wellbutrin is not the first-line treatment for patients with bipolar disorder. Your doctor will tell you the specific instructions, including which strength and how often to take this medication if you are prescribed Wellbutrin for bipolar disorder.

Take the immediate-release (IR)tablet of Wellbutrin 3 times a day as prescribed, the sustained-release (SR) tablet twice a day, and the extended-release (XL) tablet once a day. The doses of Wellbutrin SR should be at least 8 hours apart, while the doses of Wellbutrin XL should be at least 24 hours apart. Do not split, crush, or chew the sustained-release tablets. Store Wellbutrin at room temperature in a cool, dry place away from moisture and heat.

Take your medicine at approximately the same times every day. You can take this medication with or without food. Avoid taking bupropion close to bedtime if you have trouble sleeping.

In case you miss a dose, take Wellbutrin as soon as you remember. However, if it is almost time for your next dose, skip the missed dose and take the next dose at the scheduled time. Do not take extra medicine to make up for a missed dose.

Your healthcare professional will likely start you on a lower dose of Wellbutrin and increase the dose gradually. It can take several weeks or even months to get the full benefit of the medicine. Do not stop taking Wellbutrin without talking to your doctor for medical advice; you should not stop taking this medication suddenly. Talk to your doctor or pharmacist about how to properly taper this medication. Quitting Wellbutrin cold turkey can cause antidepressant discontinuation syndrome, which is present with nausea, vomiting, anxiety, agitation, and sleeping problems. If you are taking Wellbutrin for seasonal affective disorder, your healthcare provider will probably start you on the medicine in the early fall and stop it in the spring.

Antidepressant medications like Wellbutrin can cause possible side effects such as drowsiness, dizziness, headache, nausea, dry mouth, trouble sleeping, anxiety, stomach pain, vomiting, constipation, loss of appetite, weight loss, changes in taste, ringing in the ears, muscle or joint pain, and excessive sweating.

Call your healthcare provider for medical advice about side effects if they are severe or if you have new or worsening symptoms after starting Wellbutrin. Also, it is important to inform your doctor of any new or worsening mental health symptoms, such as aggressiveness, agitation, hostility, or if you feel impulsive, hyperactive, or have increased thoughts of hurting yourself or others.

Rarely, Wellbutrin can have serious side effects. Call your doctor or pharmacist immediately or seek emergency medical care if you develop:

Get emergency medical help if you have the following signs and symptoms:

Some of the risks of taking Wellbutrin are as follows:

Some people are allergic to Wellbutrin. Tell your healthcare provider if you have ever had an allergic reaction to bupropion, any of the active or inactive ingredients in bupropion tablets, or any other medications. Your pharmacist can give you a list of ingredients.

Wellbutrin can interact with other medications and cause possible side effects. Give your doctor or pharmacist a complete list of your medications. Tell them if you have taken a group of drugs called monoamine oxidase inhibitors (MAOIs) within the last 14 days.

Taking too much Wellbutrin can lead to seizures, muscle stiffness, hallucinations, rapid and uneven heartbeat, and loss of consciousness. Make sure you don’t take more than one product containing bupropion at the same time. Call 911 and seek emergency medical care or call the National Poison Control Center at 1-800-222-1222 in case of an overdose.

Wellbutrin may not be right for everyone. Tell your doctor if you have a medical history of a seizure disorder, eating disorder, high blood pressure, heart attack, heart disease, diabetes, liver disease, kidney disease, glaucoma, head injury, brain or spine tumor, depression, bipolar disorder or other mental health conditions, or if you drink alcohol regularly. Also, tell your healthcare provider if you are pregnant or nursing an infant with breast milk or if you become pregnant while on Wellbutrin.

Wellbutrin (bupropion) is an antidepressant used to help treat a number of health conditions. It comes as an immediate-release, sustained-release, or extended-release tablet that is taken orally.

One factor that makes Wellbutrin especially unique among antidepressants is that it doesn't tend to affect sexual function or reduce libido, and may even increase it. In fact, Wellbutrin is often prescribed along with other antidepressants to help counter their sexual side effects, like loss of desire.

Learn more about what Wellbutrin is and how it is used. We also share what you should know before you take this medication, including the potential side effects of Wellbutrin and drug interactions.

Wellbutrin is approved by the Food and Drug Administration (FDA) to treat major depressive disorder (MDD) and seasonal affective disorder (SAD). It is also used off-label to help with symptoms of various other conditions.

Wellbutrin may be prescribed off-label for:

Wellbutrin is also sometimes used in the treatment of certain forms of nerve pain.

Another brand of bupropion (the active ingredient in Wellbutrin), called Zyban, is used to help people quit smoking. Research shows that taking bupropion can double a person's chances of kicking their cigarette habit.

Some Wellbutrin side effects are merely bothersome and likely to disappear as your body gets used to the medication. Others are more serious and should prompt a call to your healthcare provider right away. If you have been prescribed Wellbutrin, here are some side effects to watch for.

During the first week or two of taking Wellbutrin, you may experience headaches, dry mouth, nausea, dizziness, insomnia, constipation, sore throat, and a fast heartbeat. Other common side effects for Wellbutrin, Wellbutrin SR, and Wellbutrin XL can include:

Some Wellbutrin side effects can be severe or even potentially life-threatening. Get medical help right away if you experience any of the following while taking any version of Wellbutrin:

If Wellbutrin side effects do occur, they will usually go away within a week or two of starting the medication, as your body begins to adjust. If your side effects last longer, are severe, or worsen, contact your healthcare provider right away. Your dosage may need to be changed or the medication switched to ease these effects.

Wellbutrin is often used as a first-line antidepressant in the treatment of MDD and SAD. Your healthcare provider will evaluate your symptoms and current health status to determine if it is right for you.

You may not be prescribed Wellbutrin if you have certain health conditions.

It's not clear whether Wellbutrin is safe to take during pregnancy. In animal studies, there has been some evidence of adverse effects on the fetus, but we don't yet have enough data about its effect on humans. The potential benefits of continuing Wellbutrin during pregnancy may outweigh the possible risks, but this should be discussed closely with your health provider.

Wellbutrin can be present in breast milk, so caution should be used by people who are breastfeeding. If you are lactating, your healthcare provider can help you weigh your options.

Among antidepressants, bupropion is in a category all its own—it's the only medication in its class, called norepinephrine-dopamine reuptake inhibitors (NDRIs). NDRIs boost the neurotransmitters norepinephrine and dopamine.

By contrast, selective serotonin reuptake inhibitors (SSRIs) like Prozac (fluoxetine) and Zoloft (sertraline) affect serotonin, while serotonin and norepinephrine reuptake inhibitors (SNRIs) such as Cymbalta (duloxetine) and Effexor (venlafaxine) boost norepinephrine and serotonin.

Your condition should start to improve within the first week or two of beginning Wellbutrin. You may notice positive effects, such as that you sleep better, have more energy, or your appetite has improved, for instance. Improvement of psychological symptoms, such as those related to mood, may take a bit longer—or up to eight weeks.

If you're taking bupropion to help you quit smoking, this medication works by reducing your tobacco cravings. Starting it about one week before you plan to quit gives it time to reach a therapeutic effect in your system.

How quickly your medication works may depend on what it has been prescribed to treat. For example, bupropion may also be prescribed for weight loss. One study involving 3,362 people found that many lost 5% of their body weight within eight weeks of starting a treatment containing bupropion, with more than half keeping this weight off a year later.

Wellbutrin is offered in three different formulations, and dosing varies for each version.

Your healthcare provider may prescribe a modified dosage of Wellbutrin due to possible side effects or another health concern.

Always take your medications as directed. Immediate-release Wellbutrin tablets can be broken if necessary, but they are small enough that doing so is not usually needed. The drug can be taken on an empty stomach or with food and should be stored at room temperature, protected from light and moisture.

If you happen to miss a dose of bupropion, take it as soon as you remember. Any remaining doses for the day should be taken at least six hours apart. Never take two doses of Wellbutrin at once to make up for a missed dose as this can increase your risk of experiencing a seizure or an accidental overdose.

Seizures and suicidal thoughts are two of the most serious potential side effects of Wellbutrin. Seizures are rare with this drug but may affect up to four out of every 1,000 people currently taking Wellbutrin.

For that reason, it's especially important to let your health provider know if you have or had a seizure disorder; you take any other medications that contain bupropion, such as Zyban (for quitting smoking); or you have or have had an eating disorder such as anorexia or bulimia, as seizures are more likely to occur with these disorders.

Antidepressant drugs like Wellbutrin may increase the risk of suicidal thoughts and behavior in children, teens, and young adults up to age 24—especially when first starting the medication or when there's a change in dose. If you have a child taking Wellbutrin or another depression medication, keep a close eye out for signs of self-harm or suicidal thinking.

There are a number of potential interactions that can occur when other substances are taken at the same time as Wellbutrin. Other medications may influence how bupropion works or increase the risk of side effects. These medications include:

Using Wellbutrin with alcohol may also influence the frequency and severity of side effects, including seizures and suicidal thoughts.

The most common Wellbutrin side effects tend to be the least serious and are likely to be temporary. Contact your health provider if you experience side effects that are severe, bothersome, get worse, or don't go away. Get help immediately if you have any side effects that could be serious or life-threatening.

In either case, don't stop taking Wellbutrin until you've checked with your health provider first. Going "cold-turkey" with any antidepressant can cause your symptoms to come back or get worse.

Stopping abruptly can also lead to discontinuation syndrome, an array of flu-like symptoms such as stomach upset, headache, strange sensations, and muscle aches. If you need to stop taking Wellbutrin, your provider can guide you in gradually tapering off.

Sleep, energy, or appetite may show some improvement within the first 1-2 weeks. Improvement in these physical symptoms can be an important early signal that the medication is working. Depressed mood and lack of interest in activities may need up to 6-8 weeks to fully improve.

Brand names:

All FDA black box warnings are at the end of this fact sheet. Please review before taking this medication.

Bupropion is an antidepressant medication that works in the brain. It is approved for the treatment of major depressive disorder (MDD), seasonal affective disorder (SAD), and to help people quit smoking (smoking cessation).

Symptoms of depression include:

SAD is a type of depression that occurs mainly during the autumn-winter season. Although the common term SAD is now referred to as Major Depression with Seasonal Pattern, this fact sheet will continue to use SAD as it is more commonly known.

Bupropion may also be helpful when prescribed “off-label” for bipolar disorder, attention deficit hyperactivity disorder (ADHD), and sexual dysfunction due to SSRI antidepressants. “Off-label” means that it hasn’t been approved by the Food and Drug Administration for this condition. Your mental health provider should justify his or her thinking in recommending an “off-label” treatment. They should be clear about the limits of the research around that medication and if there are any other options.

After starting bupropion, symptoms gradually decrease over a period of weeks. In MDD and SAD, sleep and other physical symptoms may improve before there is noticeable improvement in mood or interest in activities. Once symptoms are under control, MDD usually requires long-term treatment to help prevent the return of depressive symptoms. If you are using bupropion for SAD or smoking cessation, the length of your treatment may be shorter. With input from you, your health care provider will assess how long you will need to take the medicine.

Do not stop taking bupropion or change your dose without talking with your health care provider first.

Depression is also a part of bipolar illness. People with bipolar disorder who take antidepressants may be at risk for "switching" from depression into mania. Symptoms of mania include "high" or irritable mood, very high self-esteem, decreased need for sleep, pressure to keep talking, racing thoughts, being easily distracted, frequently involved in activities with a large risk for bad consequences (for example, excessive buying sprees).

If you are planning on becoming pregnant, notify your health care provider to best manage your medications. People living with MDD who wish to become pregnant face important decisions, each with risks and benefits as they relate to how the illness, medications, and risks to the fetus may interact. Untreated MDD has risks to the fetus, as well as the mother. It is important to discuss the risks and benefits of treatment with your doctor and caregivers.

Bupropion has also been evaluated for smoking cessation during pregnancy and is recommended only after other therapies have failed.

Caution is advised with breastfeeding since bupropion does pass into breast milk.

Bupropion hydrochloride is available in 3 different forms: immediate release (IR), sustained release (SR), and extended release (XL).

Bupropion IR is usually taken 2 or 3 times per day with 4-6 hours between doses. The dose usually ranges from 100 mg twice daily to 150 mg three times daily, with the last dose taken mid-afternoon.

Bupropion SR is usually taken twice daily in the morning and mid-afternoon. The dose usually ranges from 100 mg twice daily up to 200 mg twice daily.

Bupropion XL is usually taken once daily in the morning. The dose ranges from 150 mg to 450 mg.

Bupropion hydrobromide (Aplenzin®) is usually taken once daily in the morning. The dose ranges from 174 mg to 522 mg.

While there are dose ranges for each form, your health care provider will determine the form and dose that is right for you based on your response.

The dose for SAD is bupropion XL 150 mg once daily in the morning. The dose may be increased to 300 mg once daily.

The dose for smoking cessation is bupropion SR 150 mg once daily for 3 days and then twice daily for 7 to 12 weeks.

You should not take more than one product that contains bupropion, including the products that are used to quit smoking. Do not take more than your prescribed dose since higher doses may increase your risk of having a seizure. Since quickly increasing the dose of bupropion can cause seizures in some people, your doctor will slowly increase your dose.

You can take bupropion on an empty stomach or with food. The SR and XL forms should be swallowed whole — not chewed, crushed, or broken — so that the medication can work correctly in your body and to reduce the risk of serious side effects. The tablet shell from the SR and XL forms may appear in your feces. Consider using a calendar, pillbox, alarm clock, or cell phone alert to help you remember to take your medication. You may also ask a family member or friend to remind you or check in with you to be sure you are taking your medication.

For bupropion IR or SR, if you miss a dose, take it as soon as you remember. Take the remaining doses for the day at evenly spaced times at least 4 hours apart. DO NOT take 2 doses at once. You should not take more than your prescribed dose and doing so may increase your risk of having a seizure.

For bupropion XL, do not take an extra tablet to make up for the dose you forgot. Wait and take your next dose at your regular time the next day.

Avoid drinking alcohol or using illegal drugs while you are taking bupropion because the beneficial effects of the medication may be decreased and the risk of seizures may be increased. If you are dependent on drugs or alcohol and would like to stop, consult your healthcare provider for help. Abruptly stopping these substances can result in a seizure, especially when taking bupropion.

If an overdose occurs, call your doctor or 911. You may need urgent medical care. You may also contact the poison control center at 1-800-222-1222. A specific treatment to reverse the effects of fluoxetine does not exist.

Common side effects

Headache, weight loss, dry mouth, trouble sleeping (insomnia), nausea, dizziness, constipation, fast heartbeat, and sore throat. These will often improve over the first week or two as you continue to take the medication.

Rare/serious side effects

Less than 10% of patients will experience skin rash, sweating, ringing in the ears, shakiness, stomach pain, muscle pain, thought disturbances, anxiety or angle closure glaucoma (symptoms of angle closure glaucoma may include eye pain, changes in vision, swelling or redness in or around eye).

Unlike many antidepressants, bupropion does not commonly cause sexual side effects and may be selected as an alternative treatment when antidepressant-induced sexual side effects are problematic. Sexual side effects include such problems as difficulty achieving orgasm or ejaculatory delay.

In general the risk of seizures due to bupropion is low. The risk of having a seizure increases with higher than recommended doses of bupropion, a history of seizures or head injury, tumor in the brain, severe liver disease, an eating disorder, alcohol or drug dependence, or taking other drugs that can also increase your risk of having a seizure.

There is a low risk of cardiovascular adverse events associated with stimulating agents, including bupropion. This risk increases if you have heart disease, high blood pressure, previous heart attack, or irregular heartbeat, or when used with transdermal nicotine replacement products. In these cases, a thorough cardiovascular evaluation is recommended before starting this medicine.

To date, there are no known problems associated with long term use of bupropion. It is a safe and effective medication when used as directed.

Bupropion should not be taken with or within two weeks of taking monoamine oxidase inhibitors (MAOIs). These include phenelzine (Nardil®), tranycypromine (Parnate®), isocarboxazid (Marplan®), and selegiline (Emsam®).

There are several products with the active ingredient bupropion. Do not take more than one product that contains bupropion since this may increase your risk of having a seizure.

Certain medications may increase your risk of having a seizure when combined with bupropion. These include other antidepressants, antipsychotics, theophylline, isoniazid, tramadol, stimulants, steroids, hypoglycemic agents (including insulin), certain antibiotics (e.g., Cipro®), and abrupt discontinuation of benzodiazepines (e.g., Ativan®).

Notify your doctor and pharmacist if you are taking any of the following medications: phenytoin (Dilantin®), carbamazepine (Tegretol®, Equetro®), phenobarbital, cimetidine (Tagamet®), ritonavir (Norvir®), lopinavir (Kaletra™), nelfinavir (Viracept®), or efavirenz (Sustiva®). These medications can change the way your body reacts to bupropion.

Notify your doctor and pharmacist if you are taking any of the following medications: atomoxetine (Stratterra®), codeine, tamoxifen, tetrabenazine, thioridazine (Mellaril®), tramadol (Ultram®), or a tricyclic antidepressant. Bupropion can change the way your body reacts to these medications.

Sleep, energy, or appetite may show some improvement within the first 1-2 weeks. Improvement in these physical symptoms can be an important early signal that the medication is working. Depressed mood and lack of interest in activities may need up to 6-8 weeks to fully improve.

Suicidal thoughts or actions in children and adults

Depression and certain other psychiatric disorders are themselves associated with increases in the risk of suicide. Patients with major depressive disorder (MDD), both adult and pediatric, may experience worsening of their depression and/or the emergence of suicidal ideation and behavior (suicidality) or unusual changes in behavior, whether or not they are taking antidepressant medications. This risk may persist until significant remission occurs.

In short-term studies, antidepressants increased the risk of suicidality in children, adolescents and young adults when compared to placebo. Short-term studies did not show an increase in the risk of suicidality with antidepressants compared to placebo in adults beyond age 24. Adults ages 65 and older taking antidepressants have a decreased risk of suicidality. Patients, their families and caregivers should be alert to the emergence of anxiety, restlessness, irritability, aggressiveness and insomnia. If these symptoms emerge, they should be reported to the patient’s prescriber or healthcare professional. All patients being treated with antidepressants for any indication should watch for and notify their healthcare provider for worsening symptoms, suicidality and unusual changes in behavior, especially during the first few months of treatment.

Last Reviewed: January 2023

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This information is being provided as a community outreach effort of the American Association of Psychiatric Pharmacists. This information is for educational and informational purposes only and is not medical advice. This information contains a summary of important points and is not an exhaustive review of information about the medication. Always seek the advice of a physician or other qualified medical professional with any questions you may have regarding medications or medical conditions. Never delay seeking professional medical advice or disregard medical professional advice as a result of any information provided herein. The American Association of Psychiatric Pharmacists disclaims any and all liability alleged as a result of the information provided herein.

It’s also sold as a smoking cessation medication under the brand name Zyban® and for major depressive disorder under the brand name Forfivo® XL. If you’ve heard people talk about Wellbutrin for smoking, these medications are what they were talking about.

If you’ve been diagnosed with depression or seasonal affective disorder, or if you’re a smoker looking to quit, your healthcare provider may have recommended Wellbutrin (bupropion) as a treatment option.

It’s also sold as a smoking cessation medication under the brand name Zyban® and for major depressive disorder under the brand name Forfivo® XL. If you’ve heard people talk about Wellbutrin for smoking, these medications are what they were talking about.

If you’ve been diagnosed with depression or seasonal affective disorder, or if you’re a smoker looking to quit, your healthcare provider may have recommended Wellbutrin (bupropion) as a treatment option.

Below, we’ve explained exactly what Wellbutrin (bupropion) is, how it works, how long it takes to work and why it’s prescribed, and answered some common questions like: