Anastrozole
Arimidex. Aromatase inhibitor. Blocks estrogen conversion.
Overview
Arimidex. Aromatase inhibitor. Blocks estrogen conversion.
Lowers estradiol, can worsen lipids (estrogen is cardioprotective), may reduce IGF-1, can cause joint pain and mood issues if estradiol crashes too low
Compound Guide
Mechanism: Non-steroidal, reversible aromatase inhibitor. Blocks the aromatase enzyme from converting androgens to estrogens. Effect is dose-dependent and reversible -- estrogen rebounds when discontinued.
Dosage:
- On-cycle (symptom-based): 0.25-0.5 mg EOD, only when E2 symptoms are present
- High aromatisers: 0.5 mg EOD (rarely need more)
- Never use prophylactically without symptoms
Administration:
- Oral tablet, can be taken with or without food
- Tablet can be split for micro-dosing (0.25mg)
Key Notes:
- Second-line E2 management -- SERMs (Tamoxifen) are preferred first-line for gyno
- Worsens lipid profile (estrogen is cardioprotective -- lowering it increases cardiovascular risk)
- Over-use causes crashed E2: joint pain, lethargy, low libido, mood issues, bone density loss
- Reversible inhibitor: estrogen can "rebound" when stopped suddenly after prolonged use
- Symptoms warranting use: gyno onset (puffy/sensitive nipples), excessive water retention, high BP from fluid, ED/mood issues
- Does NOT need to be used on every cycle -- many users never need an AI
Usage History
Marker Interactions
Frequently Asked Questions
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Quick Reference
Category
AI
Half-Life
2 days
Detection Time
N/A