Phentermine, more commonly known by the brand names Adipex-P, Lomaira, Suprenza, Axcion, and Sentis, is a prescription weight loss medication that is used to help people lose weight by reducing appetite. It belongs to a class of drugs known as anorectics, which work by decreasing appetite and increasing feelings of fullness.
Phentermine is approved by the FDA for short-term use (a few weeks) as an adjunct to exercise, behavior modification, and a reduced-calorie diet for the treatment of obesity in people with a body mass index (BMI) of 30 or greater or in people with a BMI of 27 or greater with other obesity-related risk factors such as high blood pressure, high cholesterol, or diabetes.
While phentermine has been shown to be effective in helping people lose weight, there is some concern that long-term use of the drug may increase the risk of cancer.
In this article, we will explore the available evidence on whether phentermine can cause cancer. We will review the research studies conducted on the drug, examine the mechanisms by which phentermine may cause cancer, and discuss the potential risks and benefits of using phentermine for weight loss.
Phentermine and Cancer Risk: What Does the Research Say?
The available research on phentermine and cancer risk is limited and conflicting. Some studies suggest that phentermine may increase the risk of certain types of cancer, while others find no association between the drug and cancer risk.
A 2012 study published in the International Journal of Cancer found that women who used phentermine for weight loss had a significantly increased risk of developing breast cancer. The study analyzed data from the Nurses’ Health Study II, a large prospective cohort study that followed over 100,000 women for more than 10 years. The researchers found that women who reported using phentermine for weight loss had a 93% higher risk of developing invasive breast cancer than women who did not use the drug.
However, a 2016 study published in the Journal of Clinical Endocrinology and Metabolism found no association between phentermine use and breast cancer risk. The study analyzed data from a large healthcare database and found that women who used phentermine for weight loss did not have a higher risk of breast cancer than women who did not use the drug.
Another study published in the International Journal of Cancer in 2016 found no association between phentermine use and the risk of any type of cancer. The study analyzed data from the Cancer Prevention Study II Nutrition Cohort, which followed over 100,000 men and women for more than 20 years. The researchers found that phentermine use was not associated with an increased risk of any type of cancer.
The conflicting findings of these studies highlight the need for further research to determine whether phentermine increases the risk of cancer.
Mechanisms by Which Phentermine May Cause Cancer
The mechanisms by which phentermine may cause cancer are not well understood, and more research is needed to clarify this issue. However, there are some possible explanations based on the drug’s pharmacology.
Phentermine is a sympathomimetic amine that works by stimulating the release of norepinephrine and dopamine in the brain. These neurotransmitters increase energy expenditure and reduce appetite, which leads to weight loss. However, norepinephrine and dopamine also have other effects on the body that could potentially contribute to the development of cancer.
One possible mechanism by which phentermine may cause cancer is through its effects on the sympathetic nervous system. The sympathetic nervous system is responsible for the “fight or flight” response, which is activated in response to stress or danger. This response involves the release of norepinephrine and other stress hormones, which increase heart rate, blood pressure, and respiratory rate, among other effects.
Chronic activation of the sympathetic nervous system has been associated with an increased risk of cancer. Animal studies have shown that chronic stress and sympathetic nervous system activation can promote tumor growth and metastasis. In addition, several human studies have found an association between chronic stress and an increased risk of cancer.
Phentermine may also increase the risk of cancer by altering insulin and glucose metabolism. Phentermine has been shown to increase insulin sensitivity and glucose uptake in adipose tissue, which can lead to a decrease in blood glucose levels. However, chronic insulin resistance and hyperinsulinemia have been linked to an increased risk of several types of cancer, including breast, colon, and pancreatic cancer.
Furthermore, phentermine has been shown to increase oxidative stress and inflammation, both of which can contribute to the development of cancer. Oxidative stress occurs when there is an imbalance between the production of reactive oxygen species (ROS) and the body’s ability to detoxify them. Chronic oxidative stress can damage DNA and other cellular components, leading to mutations and cellular damage that can promote cancer development. Inflammation is also a known risk factor for cancer, as chronic inflammation can promote tumor growth and metastasis.
Finally, phentermine may increase the risk of cancer by promoting angiogenesis, which is the formation of new blood vessels. Angiogenesis is a key step in tumor growth and metastasis, as tumors require a blood supply to grow beyond a certain size. Phentermine has been shown to increase the expression of vascular endothelial growth factor (VEGF), a key regulator of angiogenesis. Therefore, it is possible that long-term use of phentermine could promote the growth and spread of tumors by increasing angiogenesis.
Overall, the mechanisms by which phentermine may cause cancer are not well understood, and more research is needed to clarify this issue. While there are several potential mechanisms by which phentermine could increase the risk of cancer, it is important to note that these are theoretical and have not been conclusively demonstrated in human studies.
Potential Risks and Benefits of Using Phentermine for Weight Loss
The potential risks and benefits of using phentermine for weight loss should be carefully considered before deciding to use the drug. While phentermine can be an effective tool for promoting weight loss in people who are obese, it is not a magic bullet and should be used in conjunction with a healthy diet and exercise program.
Some of the potential benefits of using phentermine for weight loss include:
• Effective weight loss: Phentermine has been shown to be effective in promoting weight loss in people who are obese.
• Improved health outcomes: Losing weight can improve several obesity-related health conditions, including high blood pressure, high cholesterol, and type 2 diabetes.
• Improved quality of life: Losing weight can improve self-esteem, mood, and overall quality of life.
The decision to use phentermine for weight loss should be based on a careful evaluation of the potential risks and benefits in your individual case, taking into account factors such as your overall health status, medical history, and any other medications you are taking. It is important to have an open and honest conversation with your doctor or healthcare provider about your weight loss goals and any concerns you may have about the use of phentermine. They will be able to provide personalized advice based on your individual circumstances.
