Do I Need an Aromatase Inhibitor (AI)?

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If you’re considering TRT or you’re already on it, you may have questions about aromatase inhibitors.

Aromatase inhibitors (AIs) reduce Estrogen levels by blocking an enzyme called aromatase. This enzyme is responsible for converting other hormones into Estrogen.

AIs are commonly used to treat hormone-receptive positive breast cancer. They can also be prescribed to help men on TRT avoid high Estrogen.

In men, elevated Estrogen levels can lead to symptoms like erectile dysfunction, infertility, weight gain, and muscle loss.

In severe cases, it can cause a condition called gynecomastia where men grow breast tissue.

While some men on TRT benefit from AI therapy, these medications are not appropriate for everyone. We’ll go over what types of patients benefit from AIs and why.

What Is an Aromatase Inhibitor?

As we touched on above, AIs block an enzyme in fat tissue called aromatase.

This enzyme helps convert other hormones like Testosterone into Estrogen. By stopping this process, AI medications reduce Estrogen levels.

AI Medications include:

Anastrozole
Exemestane
Letrozole

Historically, aromatase inhibitors have been used to treat a specific type of breast cancer that is hormone receptive to Estrogen. This means Estrogen helps the cancer grow. As a result, blocking Estrogen production helps to slow the cancer’s progress.

Hormone-receptive breast cancer is most common in women, but occasionally men develop this disease, as well.

More recently, providers have used AIs as part of a TRT plan for men who struggle with excess Estrogen.

Why Do Aromatase Inhibitors Help Some TRT Patients?

Hormones levels are connected within the body. When you raise levels for one hormone, you may also raise levels for another.

Because the body converts a portion of Testosterone into Estrogen, higher T levels can lead to a corresponding increase in Estrogen levels.

This isn’t an issue for every patient, but it’s important to know the signs.

Symptoms of elevated Estrogen in men include:

Erectile dysfunction
Decreased sex drive
Infertility
Weight gain
Muscle loss
Fatigue
Depression

Men on TRT who have healthy T levels but still experience the symptoms above may be dealing with excess Estrogen.

In those cases, an AI can decrease Estrogen levels and ease high-Estrogen symptoms.

What Happens if High Estrogen Levels are Left Unchecked?

If elevated Estrogen goes untreated in men, it can lead to worsening symptoms over time.

Eventually, men may experience more extreme conditions related to Estrogen. These include:

Gynecomastia (the growth of male breast tissue)
High blood pressure
Blood clots
Hypocalcemia (abnormally low calcium levels)
Obesity
Worsening of preexisting conditions like epilepsy
Increased risk of developing breast and prostate cancer

Do All Men on TRT Need Aromatase Inhibitors?

No, every man on TRT does not require an aromatase inhibitor to regulate Estrogen. Many men don’t experience elevated Estrogen levels while on TRT.

Defy Medical creates individualized plans that match the needs of each patient. We require comprehensive blood panels to track not just Testosterone levels, but also Estrogen levels and other markers of health.

The Estrogen Sensitive Test for Men

Men’s bodies produce Estrogen, but in much lower levels than women. Because of this, Defy Medical requires an Estradiol Sensitive test, or E2 sensitive test, in the Men’s Health lab panel.

The Estradiol Sensitive test is able to measure Estrogen levels more precisely, making it more useful for men.

The acceptable adult range for Estrogen in men is 8.0−35.0 ph/mL according to LabCorp. Quest Diagnostics has a similar reference point of less than 29 ph/mL.

While these figures are useful, our Care Team also takes symptoms and how you’re feeling into account when determining optimized hormone ranges.

How Defy Medical Prescribes AIs

Our policy is to provide male patients with an optional script for an AI, typically Anastrozole.

If a patient begins experiencing symptoms of elevated Estrogen or if his lab work discovers high E levels, he can fill the script and begin taking the AI.

By providing the script at the beginning, we aim to limit the discomfort and wait times associated with starting a new medication.

For male patients who never experience complications from high Estrogen, we don’t recommend taking an AI.

Defy Medical believes in empowering patients to take control of their health and make their own decisions.

If patients have an aversion to AI medications, they can work with their Defy Medical provider to come up with alternative solutions.

Other Types of Estrogen Blockers

Aromatase Inhibitors are one type of Estrogen blocker. Another type is called a Selective Estrogen Receptor Modulator (SERM).

SERMs block Estrogen by binding to Estrogen receptors within the hypothalamus and pituitary gland. In doing so, they reduce the effects of Estrogen in the body.

SERM medications include:

Clomiphene
Tamoxifen

In addition to helping with the effects of high Estrogen, SERMs are often used to support fertility and Testosterone production in men.

How do SERMs Support Men’s Health?

Excess Estrogen has a negative impact on the production of gonadotropin-releasing hormone (GnRH), follicle-stimulating hormone (FSH), and luteinizing hormone (LH).

GnRH is responsible for stimulating the release of FSH and LH.
FSH stimulates the testes to produce sperm, which maintains function and fertility.
LH stimulates the testes to produce Testosterone.

SERMs can block the effect of Estrogen and improve the production of GnRH, FSH, and LH.

While SERMs typically aren’t effective enough to treat a Testosterone deficiency on their own, they may reduce Estrogen, support Testosterone production, and improve fertility.

Comprehensive Care with Defy Medical

For some men, aromatase inhibitors are necessary to help them feel their best.

Defy Medical offers individualized TRT plans based on your unique levels, symptoms, and experiences with treatment.

Our expert providers work with you to create a TRT protocol that fits your lifestyle and goals. This plan may include an AI, as well as other support medications like HCG, depending on your needs.

We also offer convenient telemedicine appointments and easy online ordering of medications.

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