Hormone Optimization

Anastrozole / Arimidex

Potent non-steroidal aromatase inhibitor (AI) utilized off-label to manage elevated estradiol (E2) levels during TRT. Clinical goal: Maintain E2 within physiological range without suppressing to levels that negatively impact bone density, libido, and joint health.

DRUG CLASS
Non-steroidal Aromatase Inhibitor
PRIMARY ACTION
Inhibits CYP19A1 Enzyme
KEY RISK
Estrogen Crash (<10 pg/mL)

Dosing Protocols & Titration

Select an administration method to view recommended starting protocols. Dosing is highly individual.

Configuration

⚠

Start LOW. It is easier to titrate up than to recover from crashed estrogen.

Standard Oral Protocol

Tablet / Capsule Form
0.25 - 0.5mg
Per Dose Frequency

Administration Timing

Take 12-24 hours post-testosterone injection to align peak AI levels with peak aromatization windows.

Standard Start

0.25mg taken twice weekly (e.g., day after injections).

Conservative Start

0.125mg taken "as needed" based on confirmed high E2 symptoms.

Pharmacokinetics (Oral)

Half Life ~40-50 Hours
Peak Plasma 2 Hours
Steady State 7 Days

Compounded Injectable

Co-formulated with Testosterone
Ratio Based
mg Anastrozole : mg Testosterone

Mechanism

Commonly compounded directly into the testosterone ester oil. This ensures compliance but removes the ability to titrate the AI independently from the Test dose.

Common Ratio A

1 mg : 200 mg

1mg Anastrozole per 200mg Test (High Risk of Crash)

Common Ratio B

0.1 mg : 200 mg

"Micro-dosing" - Much safer starting point.

!

Warning: If E2 crashes on compounded T+AI, the patient must switch to plain Testosterone immediately to allow recovery.

Dose vs. Estrogen Suppression

*Theoretical reduction based on 1mg daily load (Clinical Data). TRT dosing uses micro-doses to avoid the >80% suppression zone.

Pharmacology & Mechanism

Anastrozole is a selective, non-steroidal inhibitor of the aromatase enzyme (CYP19A1). In men, aromatase is primarily found in adipose tissue.

  • 01
    Potency 1mg daily can suppress estradiol by ~80%. This is typically too potent for TRT, necessitating fractional dosing (0.125mg - 0.5mg).
  • 02
    Rebound Effect Unlike suicidal inhibitors (Exemestane), Anastrozole binds reversibly. Upon cessation, a "rebound" in estrogen can occur as the enzyme becomes active again. Tapering is often recommended.
  • 03
    Lipid Impact AI use often negatively impacts lipid profiles (Lower HDL). This is a primary reason to minimize dose frequency.

Clinical Monitoring Matrix

Distinguishing between High E2 and Crashed E2 is critical, as symptoms often overlap.

High Estradiol

OVER-AROMATIZATION
  • Water Retention / Bloating
  • High Blood Pressure
  • Emotional Lability (Crying/Anger)
  • Sensitive Nipples / Gyno
  • Oily Skin / Acne

ACTION:

Confirm with bloodwork (E2 Sensitive LC/MS). Introduce AI at lowest effective dose (0.125mg-0.25mg).

Crashed Estradiol

AI OVER-USE
  • Joint Pain / Clicking (Dryness)
  • Loss of Libido / ED
  • Fatigue / Lethargy
  • Anhedonia (Flat Mood)
  • Dehydration symptoms

ACTION:

STOP AI immediately. Increase Testosterone dose or administer HCG/DHEA to drive aromatization. Recovery takes weeks.

Standard Bloodwork Timeline

0
Baseline
Pre-TRT
6
Week 6
First Check
12
Week 12
Titration
26
6 Months
Stability