From the FDA Drug Label
Drugs Metabolized by CYP2D6 Bupropion and its metabolites (erythrohydrobupropion, threohydrobupropion, hydroxybupropion) are CYP2D6 inhibitors Therefore, coadministration of bupropion hydrochloride extended-release tablets (XL) with drugs that are metabolized by CYP2D6 can increase the exposures of drugs that are substrates of CYP2D6. Such drugs include certain antidepressants (e.g., venlafaxine, nortriptyline, imipramine, desipramine, paroxetine, fluoxetine, and sertraline), When used concomitantly with bupropion hydrochloride extended-release tablets (XL), it may be necessary to decrease the dose of these CYP2D6 substrates, particularly for drugs with a narrow therapeutic index.
Bupropion and Venlafaxine Interaction:
- Bupropion can be taken with venlafaxine, but it may be necessary to decrease the dose of venlafaxine due to the increased exposure of venlafaxine caused by bupropion's inhibition of CYP2D6.
- Patients should be closely monitored for adverse reactions, and the dose of venlafaxine should be adjusted accordingly 1.
From the Research
Bupropion and venlafaxine can be taken together, but this combination should only be used under close medical supervision due to the potential risks of serotonin syndrome, seizures, and elevated blood pressure. This approach combines two different antidepressant mechanisms - bupropion primarily affects dopamine and norepinephrine, while venlafaxine works on serotonin and norepinephrine. For some patients with treatment-resistant depression, this combination may provide better symptom relief than either medication alone, as seen in a case report where a patient responded favorably to combination therapy with venlafaxine and bupropion 2. However, the combination carries increased risks, and patients should be monitored closely for side effects.
Some key points to consider when taking bupropion and venlafaxine together include:
- Starting at lower doses with gradual increases while monitoring for side effects
- Regular blood pressure checks
- Immediately reporting any unusual symptoms like severe headache, confusion, tremors, or fever
- Discussing complete medical history and all other medications with the doctor, as certain conditions (seizure disorders, eating disorders, recent head trauma) and medications may make this combination unsafe
- Being aware of the potential for serotonin syndrome, which can be fatal, as reported in a case where a patient developed serotonin syndrome after taking bupropion and an SSRI 3
It's also important to note that bupropion is a moderate inhibitor of CYP2D6, which can lead to pharmacokinetic interactions with other medications, such as venlafaxine, which is metabolized by CYP2D6 4. However, the most recent and highest quality study on this topic is from 2019, which provides a comprehensive review of serotonin and norepinephrine reuptake inhibitors, including venlafaxine, but does not specifically address the combination of bupropion and venlafaxine 5. Overall, the decision to take bupropion and venlafaxine together should be made on a case-by-case basis, taking into account the individual patient's medical history, current medications, and potential risks and benefits.