AASUser24
New member
I came across this comparison between Aromasin (Exemestane) and Arimidex (Anastrozole) some time ago, and it was so insightful that I saved it. I hope you find it as useful as I did.
A Few Points to Keep in Mind:
Before diving into the specifics of Aromasin and Arimidex, it’s important for anyone unfamiliar with cholesterol to understand the clinical differences between HDL and LDL. This topic is relevant, especially since the impact of these drugs on cholesterol can be a significant part of the discussion. Here’s a link to a great overview of cholesterol levels — understanding this will help you make a more informed decision when considering an aromatase inhibitor (AI).
Important Considerations:
- Both Aromasin and Arimidex were initially developed for cancer treatment in women . However, they behave differently in men, and this distinction is critical. Some of you might reference the Lancet study from a few years ago, but it's important to note that the study was conducted exclusively with women, so the results may not apply to male users.
Aromasin (Exemestane): A Type-I Aromatase Inhibitor
Aromasin, also known as Exemestane, is a Type-I aromatase inhibitor, often referred to as a “suicidal inhibitor.” It works by permanently binding to and deactivating the aromatase enzyme, leading to a significant reduction in estrogen production. In men, Aromasin has been shown to:
- Reduce estrogen levels by approximately 70-80% (with a single 25mg dose).
- Increase testosterone by up to 60% .
- Increase insulin-like growth factor (IGF-1) .
- Minimally affect cholesterol levels, which is a positive when compared to some other AIs like Letrozole (Femara).
In one study of healthy men, after 24 hours of a 25mg dose of Aromasin, estrogen was suppressed by 70-80%. Estrogen levels remained 40% below baseline after 72 hours, and returned to baseline after 120 hours. The half-life in men is approximately 9 hours , so taking Aromasin once a day is effective.
Recent studies confirm that Aromasin is well-tolerated and provides substantial suppression of estrogen without significantly affecting lipids or IGF-1. It’s a solid choice for users aiming for effective estrogen control during cycles.
Arimidex (Anastrozole): A Type-II Aromatase Inhibitor
Arimidex, or Anastrozole, is a Type-II aromatase inhibitor that works by reversibly binding to the aromatase enzyme , thereby inhibiting the conversion of testosterone into estrogen. In women, Arimidex can reduce circulating estrogen by nearly 85% , but in men, the suppression is usually around 50% with a daily dose of 1mg.
Some key points about Arimidex:
- Estrogen rebound : Once you stop taking Arimidex, the aromatase enzyme is free to convert androgens back into estrogen, which can lead to a spike in estrogen levels and associated side effects like gynecomastia or water retention.
- Testosterone boost : Arimidex can increase testosterone by about 58% in men.
- Lipids : The effects of Arimidex on cholesterol are generally minimal. Research has shown that Arimidex does not significantly alter HDL or LDL levels, though some studies have shown a slight increase in cholesterol for patients on Arimidex, as seen in the ATAC trial.
For those using Arimidex to manage gynecomastia, studies suggest it may be effective in younger men with recent onset of the condition. However, it appears to have limited effectiveness in individuals with more established gynecomastia.
A typical dose for men using Arimidex is 0.25-0.5mg every other day (EOD), with adjustments based on estrogen levels.
Key Takeaways:
- Aromasin (Exemestane) is a “suicidal” AI that deactivates the aromatase enzyme permanently, leading to sustained estrogen suppression. It also has a shorter half-life (around 10 hours) and is typically dosed 12.5mg daily .
- Arimidex (Anastrozole) , a reversible inhibitor, has a longer half-life (around 47 hours) and is often dosed 0.25-0.5mg every other day (EOD).
- Both AIs are effective, but Aromasin may be more consistent in suppressing estrogen, while Arimidex has a quicker onset of action but requires careful management to prevent estrogen rebound.
In my research, I’ve found both Aromasin and Arimidex to be excellent choices for controlling estrogen on a steroid cycle. However, based on available data, Aromasin is a solid option for daily use due to its consistent effects and more favorable impact on lipids. Arimidex, on the other hand, may be better suited for individuals seeking rapid estrogen suppression with careful dosing to prevent estrogen rebound.
Share your experiences with either Aromasin or Arimidex.
A Few Points to Keep in Mind:
Before diving into the specifics of Aromasin and Arimidex, it’s important for anyone unfamiliar with cholesterol to understand the clinical differences between HDL and LDL. This topic is relevant, especially since the impact of these drugs on cholesterol can be a significant part of the discussion. Here’s a link to a great overview of cholesterol levels — understanding this will help you make a more informed decision when considering an aromatase inhibitor (AI).
Important Considerations:
- Both Aromasin and Arimidex were initially developed for cancer treatment in women . However, they behave differently in men, and this distinction is critical. Some of you might reference the Lancet study from a few years ago, but it's important to note that the study was conducted exclusively with women, so the results may not apply to male users.
Aromasin (Exemestane): A Type-I Aromatase Inhibitor
Aromasin, also known as Exemestane, is a Type-I aromatase inhibitor, often referred to as a “suicidal inhibitor.” It works by permanently binding to and deactivating the aromatase enzyme, leading to a significant reduction in estrogen production. In men, Aromasin has been shown to:
- Reduce estrogen levels by approximately 70-80% (with a single 25mg dose).
- Increase testosterone by up to 60% .
- Increase insulin-like growth factor (IGF-1) .
- Minimally affect cholesterol levels, which is a positive when compared to some other AIs like Letrozole (Femara).
In one study of healthy men, after 24 hours of a 25mg dose of Aromasin, estrogen was suppressed by 70-80%. Estrogen levels remained 40% below baseline after 72 hours, and returned to baseline after 120 hours. The half-life in men is approximately 9 hours , so taking Aromasin once a day is effective.
Recent studies confirm that Aromasin is well-tolerated and provides substantial suppression of estrogen without significantly affecting lipids or IGF-1. It’s a solid choice for users aiming for effective estrogen control during cycles.
Arimidex (Anastrozole): A Type-II Aromatase Inhibitor
Arimidex, or Anastrozole, is a Type-II aromatase inhibitor that works by reversibly binding to the aromatase enzyme , thereby inhibiting the conversion of testosterone into estrogen. In women, Arimidex can reduce circulating estrogen by nearly 85% , but in men, the suppression is usually around 50% with a daily dose of 1mg.
Some key points about Arimidex:
- Estrogen rebound : Once you stop taking Arimidex, the aromatase enzyme is free to convert androgens back into estrogen, which can lead to a spike in estrogen levels and associated side effects like gynecomastia or water retention.
- Testosterone boost : Arimidex can increase testosterone by about 58% in men.
- Lipids : The effects of Arimidex on cholesterol are generally minimal. Research has shown that Arimidex does not significantly alter HDL or LDL levels, though some studies have shown a slight increase in cholesterol for patients on Arimidex, as seen in the ATAC trial.
For those using Arimidex to manage gynecomastia, studies suggest it may be effective in younger men with recent onset of the condition. However, it appears to have limited effectiveness in individuals with more established gynecomastia.
A typical dose for men using Arimidex is 0.25-0.5mg every other day (EOD), with adjustments based on estrogen levels.
Key Takeaways:
- Aromasin (Exemestane) is a “suicidal” AI that deactivates the aromatase enzyme permanently, leading to sustained estrogen suppression. It also has a shorter half-life (around 10 hours) and is typically dosed 12.5mg daily .
- Arimidex (Anastrozole) , a reversible inhibitor, has a longer half-life (around 47 hours) and is often dosed 0.25-0.5mg every other day (EOD).
- Both AIs are effective, but Aromasin may be more consistent in suppressing estrogen, while Arimidex has a quicker onset of action but requires careful management to prevent estrogen rebound.
In my research, I’ve found both Aromasin and Arimidex to be excellent choices for controlling estrogen on a steroid cycle. However, based on available data, Aromasin is a solid option for daily use due to its consistent effects and more favorable impact on lipids. Arimidex, on the other hand, may be better suited for individuals seeking rapid estrogen suppression with careful dosing to prevent estrogen rebound.
Share your experiences with either Aromasin or Arimidex.
