Do Bupropion and Phentermine work together? (1 side effect)

In this article, we will answer: “Do Bupropion and Phentermine work together?”. We will also discuss the potential side effects and risks of this combination and some suitable alternatives. 

Do Bupropion and Phentermine work together?

It is not generally recommended to take Bupropion and Phentermine together. In a study, it has been reported that the combination of Bupropion and Phentermine may cause heart valve fibrosis (1).

Hence, the combination of Bupropion and Phentermine doesn’t work together. 

Bupropion (Wellbutrin) is an antidepressant drug that acts by inhibiting the reuptake of norepinephrine and dopamine (2).

Bupropion is used in the treatment for the following conditions (2):

  • Adult depression
  • Seasonal affective disorder
  • Smoking cessation
  • Anti-depressant-induced sexual dysfunction
  • Attention-deficit/hyperactivity disorder (ADHD)
  • Depression associated with bipolar disorder
  • Obesity

Phentermine is a sympathomimetic amine that exerts its pharmacological effects within the central nervous system to suppress appetite. It results in a 3-8% weight loss.

Phentermine is used in the treatment of the following conditions (4):

  • Obesity (Approved for age 17 years or older)

Why you should not take Bupropion and Phentermine together? 

 Bupropion has been documented to increase the levels of serotonin in the brain (3).

Phentermine has an inhibitory effect on the uptake of serotonin by red blood cells (4). Consequently, the co-administration of Phentermine and Bupropion has the potential to elevate the circulating serotonin levels, which in turn may contribute to the development of heart valve fibrosis (1).

Heart valve fibrosis is the thickening or scarring of one or more heart valves. It can lead to symptoms such as shortness of breath, fatigue, heart palpitations and swelling in ankles, feet or abdomen. 

Individual studies on Bupropion and Phentermine have shown that both drugs can be effective in promoting weight loss. However, limited research exists on their combined effect. 

While Bupropion is a proven antidepressant, Phentermine’s impact on mood is more related to its stimulant effects, not a direct antidepressant action. The synergistic effects of these drugs on depression remain unexplored. 

Always seek the advice of your healthcare expert when it comes to drug selection and possible risks and benefits.

What are the Potential Risks of Taking Bupropion and Phentermine Together? 

Combining Bupropion and Phentermine can pose health risks which may include (2,4):

  • Increased risk of seizure
  • High blood pressure
  • Tachycardia
  • Tremors
  • Dry mouth 
  • Insomnia

What to do if you have taken Bupropion and Phentermine together?

If you have already taken Bupropion and Phentermine together, it is important to reach out to your doctor immediately. They can provide guidance, assess any potential risk or side effects, and if necessary, adjust your medication or monitor your health closely to avoid complications. 

Be observant of symptoms like increased heart rate, high blood pressure, restlessness, excessive sweating, muscle twitching, or tremors. In cases of severe reactions like shortness of breath, chest pain, or extreme anxiety, seek emergency medical attention. 

In the future, it is important to take necessary precautions by avoiding self-prescribing and scheduling regular follow-ups. 

What are the alternatives to taking Bupropion and Phentermine together?

Phentermine is commonly paired with Topiramate as an alternative for weight management, enhancing the drug’s efficacy while mitigating side effects. Topiramate is an antiepileptic drug which promotes weight loss by suppressing appetite and altering taste perception (5). 

Bupropion and Naltrexone combination is often prescribed to aid in weight loss. The combination functions synergistically in the mesolimbic dopamine circuit and hypothalamus to elevate satiety, reduce food intake, and enhance energy expenditure (6). 

The best alternative treatment is highly individualized and should be ascertained by a qualified healthcare professional. Always follow the doctor’s advice and directions when it comes to combinations like these. 


In this given article, we talked about taking Bupropion and Phentermine at the same time. It is recommended not to take Bupropion and Phentermine together as it may lead to heart valve fibrosis. If you have already taken Bupropion and Phentermine together, reach out to your doctor immediately. 

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