Functions & Traits:

Letrozole is an Aromatase Inhibitor (AI) that blocks the aromatase enzyme, reducing estrogen production and serum estrogen levels in the body. This is beneficial for both breast cancer patients, as many cancers thrive on estrogen, and anabolic steroid users, for whom excess estrogen can lead to side effects like gynecomastia and water retention. Letrozole also promotes natural testosterone production by boosting Luteinizing Hormone (LH) and Follicle Stimulating Hormone (FSH), though it is generally paired with testosterone therapy rather than used as a standalone treatment for low testosterone.

Effects of Letrozole:

For breast cancer patients, Letrozole starves cancer by lowering estrogen, often replacing Nolvadex as a first-line treatment. Once cancer is in remission, a SERM like Nolvadex may be used to prevent recurrence.

For steroid users, Letrozole offers powerful anti-estrogen protection, reducing gynecomastia and water retention, which can also prevent blood pressure issues caused by excess water. Many anabolic steroids aromatize, promoting estrogen increase, but Letrozole helps prevent estrogenic side effects, particularly when steroids like Dianabol and testosterone are used. However, Letrozole and other AI’s can adversely affect cholesterol, especially when combined with aromatizing steroids. In cases where cholesterol is a concern, SERM’s like Nolvadex may be preferable since they support healthier cholesterol levels.

Although Letrozole can promote natural testosterone production, it’s usually not recommended for Post Cycle Therapy (PCT), as it suppresses estrogen too significantly, which can hinder normalization. Estrogen plays a key role in immune health and cholesterol management, making SERM’s a better PCT choice.

Letrozole Administration:

1. Breast Cancer Treatment: A 2.5mg daily dose is standard and continues until remission. Patients may then switch to Nolvadex for maintenance.
2. Steroid Users: For estrogenic side effects, 0.5-1mg every other day is usually sufficient. A higher dose of 2.5mg may be used for 7-14 days if gynecomastia symptoms appear, then taper to a lower dose. For competitive bodybuilders, a full 1mg daily dose in the last 7-14 days pre-competition can improve muscular dryness and appearance. Extended high dosing should be avoided to prevent fatigue and other adverse effects.