What is Anastrozole?

Anastrozole is the active compound in Arimidex, originally developed to treat breast cancer in post-menopausal women. It belongs to a class of drugs called aromatase inhibitors. In fitness and performance circles, it's widely used to keep oestrogen levels in check during steroid cycles.

Quick Facts

How Does It Work?

Anastrozole blocks the aromatase enzyme, which is responsible for converting testosterone into oestrogen. Less aromatase activity means lower oestrogen levels in the body. This helps prevent oestrogen-related side effects that can occur when using anabolic steroids.

What It's Used For

• Controlling oestrogen levels during anabolic steroid cycles
• Preventing water retention and bloating caused by high oestrogen
• Reducing the risk of gynaecomastia (breast tissue development in men)

What to Expect

Users typically notice reduced water retention and a leaner, drier appearance within the first week of use. Mood and energy can also stabilise when oestrogen is kept at a healthy level rather than being completely suppressed. It works best when used reactively or as a preventative measure alongside aromatising compounds.

Possible Side Effects

• Joint aches and stiffness if oestrogen is driven too low
• Reduced libido from excessively low oestrogen
• Fatigue and low mood if oestrogen is over-suppressed

Cycle & Dosage Notes

Anastrozole is typically run alongside aromatising steroids such as testosterone, starting at 0.5mg every other day and adjusting based on bloodwork. It is not needed during post-cycle therapy and should be tapered off as the steroid cycle ends. Blood tests are the best way to dial in the right dose and avoid crashing oestrogen too low.

Storage

Keep at room temperature (15–25°C), away from light and moisture. Leave in the original packaging.

This info is for research and educational purposes only. Check the laws in your country before ordering.