How long does it take bupropion to work?

In this article:

• How long does it take bupropion to work?
• Influencing factors
• Dosage
• Contraindications
• The bottom line

In this article

• How long does it take bupropion to work?
• Influencing factors
• Dosage
• Contraindications
• The bottom line

Bupropion, commonly marketed under the brand names Wellbutrin SR, Wellbutrin XL, and Zyban, is an oral medication used for treating adult depression and seasonal affective disorder (SAD). SAD is a form of depression that occurs in a recurrent seasonal pattern and is more common or severe during winter.

Bupropion is also approved by the Food and Drug Administration (FDA) as a medication for aiding smoking cessation. It usually starts improving some symptoms within the first one to two weeks of taking it. However, it may take longer to effectively treat all symptoms of depression.

“Bupropion works by increasing the activity of two chemicals in the brain (dopamine and norepinephrine), which are important for mood,” says Shaina Schwartz, Pharm.D., an assistant professor of pharmacy clinical studies in High Point University’s Fred Wilson School of Pharmacy. She explains that one of the theories behind why people develop depression is that their levels of these chemicals are too low, so bupropion can be used to treat depression by restoring these levels.

How long does it take for bupropion to work? 

“Bupropion typically takes about one to two weeks to start showing effects, but it can take up to six weeks to feel the full benefits,” says Brian Zachariah, MD, a board-certified psychiatrist at Mindpath Health. While symptoms like energy, sleep, and appetite may improve earlier, others, like lack of interest in day-to-day activities and depressed mood, may take longer to improve. 

Dr. Zachariah also explains that the onset of action can vary depending on the dosage and the form of the medication taken. Bupropion is available in three forms: immediate-release (IR), sustained-release (SR), and extended-release (XL).

The IR form starts to show effects within a few hours and is taken multiple times a day. The SR form begins to show effects within three to four hours and is taken twice a day. The XL form starts to show effects within five to six hours and is taken once a day to provide a steady level of the drug throughout the day.
Improvement in certain symptoms is an indication that bupropion is working for you. “Individuals should notice a gradual improvement in their symptoms of depression or other conditions being treated, such as a better mood, increased energy levels, and improved focus and motivation,” Dr. Zachariah says. 

Additionally, he notes that after starting bupropion, some people may experience some common side effects, such as constipation, dry mouth, insomnia, and headaches, which often improve over time.

What can affect how long bupropion takes to work?

Different factors can affect bupropion’s absorption, or how long it takes to work. According to Dr. Zachariah, this includes food intake, age, liver function, and concurrent use of other medications. He explains that:

• Taking the medication with food can slow down its absorption (however, you may need to take it with food if the medicine upsets your stomach). 
• Age and liver function can influence how the body metabolizes the drug. 
• Another consideration is bariatric surgery, which can change the way medications are absorbed in the gastrointestinal tract. This can lead to decreased effectiveness of bupropion, as the altered anatomy may affect its bioavailability.

It is best to avoid drinking coffee while on bupropion as this medication may not mix well with caffeine, the main active ingredient in coffee. Combining both may lead to worsened symptoms of depression, anxiety, trouble sleeping, and, in rare cases, toxicity and seizures.

Also, some herbs or dietary supplements may affect bupropion’s onset of action or effectiveness. For instance, the medication may be less effective when taken with the dietary supplement St. John’s wort.

Dr. Shwartz also notes that Wellbutrin works through a process called “reuptake inhibition” of the neurotransmitters dopamine and norepinephrine. The brain takes time to adjust to these changes, so many people may not see the effects of Wellbutrin for about a month.

There are no standardized or specific methods to make bupropion kick in faster. But, it is advisable to use it consistently and as prescribed by a healthcare professional. Dr. Zachariah also suggests maintaining a healthy lifestyle, including regular exercise and a balanced diet. These can support overall well-being and potentially enhance the medication’s effectiveness.

What is the standard bupropion dosage?

“The typical total daily dose for bupropion is 300 mg,” Dr. Schwartz says. This dose is often prescribed both for treating major depressive disorder (MDD) and for quitting smoking. Also, it may be dosed once daily or multiple times daily, depending on the formulation you are prescribed.

Who should avoid taking bupropion?

Aside from its FDA-approved uses, bupropion has other off-label uses, including treating depression related to attention deficit hyperactivity disorder (ADHD), bipolar disorder, and obesity. But despite its broad use cases, it may not be ideal for everyone. 

People who should avoid taking bupropion (unless otherwise stated by their healthcare provider) include: 

• People with seizure disorders
• People with severe head injury or brain tumor
• People who have a history of eating disorders like bulimia or anorexia nervosa
• People who are taking medications like linezolid, monoamine oxidase inhibitors, and methylene blue
• People with high blood pressure (bupropion can cause an increase in blood pressure)
• People who are allergic to bupropion or other ingredients in this medication.

If your healthcare provider is considering prescribing you bupropion, let them know if you are pregnant, want to get pregnant, or are breastfeeding. Also, feel free to ask them questions about the safety of alcoholic beverage consumption while on this medication. This is because alcohol may worsen its adverse effects.

Drug interactions

Discuss any medications you are currently taking—both prescription and non-prescription medications—to know if they are safe to take together with bupropion. Notably, some drugs that have a high chance of interacting with this medication include:

• Ticlopidine and clopidogrel: These medications are inhibitors of CYP2B6, an enzyme that plays an important role in the metabolism of many clinical drugs, including bupropion. This means they can prevent or delay the metabolism of bupropion.
• Lopinavir and ritonavir: These medications induce or support the action of CYP2B6, which means they may speed up the metabolism of bupropion. 
• Dopaminergic drugs: It may be best to avoid taking bupropion with dopaminergic drugs like levodopa and amantadine. Bupropion may exert similar effects as these drugs, activating dopamine receptors in the brain. When used together, the combined dopamine agonist effects may lead to central nervous system toxicity. 
• Monoamine oxidase inhibitors (MAOIs): MAOIs prevent the breakdown of brain chemicals like dopamine and norepinephrine, helping regulate mood. Bupropion may affect how these medications work and may increase the risk of hypertensive reactions. 

The bottom line

Wellbutrin (bupropion) typically starts working within one to two weeks of taking it. However, improvements in some symptoms may not be noticed until after about six weeks of taking it. How fast it acts and its effectiveness also varies from person to person, depending on factors like food consumption, certain medications or supplements ingested with it, and age. 

If you experience serious side effects while taking this medication or feel like it’s not improving your symptoms, it’s best to speak with your healthcare provider. They can properly reassess you, suggest a different treatment plan, and offer medical advice.