Known as an aromatase inhibitor (AI), the drug Arimidex blocks the aromatase enzyme and prevents it from producing estrogen in the body. Arimidex is used clinically in women who are suffering from breast cancer. It is administered to them to halt the progression of the cancerous cells. However, bodybuilders and athletes include Arimidex in their anabolic steroid cycles as it is known to increase testosterone levels slightly as well as having estrogen-reducing properties.
Anyone using anabolic steroids will suffer from a number of unwanted side effects. These include acne, gynecomastia, water retention, and other symptoms. These side-effects are caused by the anabolic steroids converting to estrogen by way of the aromatase enzyme, the process is known as ‘aromatizing’. Studies have shown that 5mg and 1mg doses of Arimidex decrease this process by around 50%. A 1mg dose of Arimidex increased testosterone levels by 58%. These studies, and in particular one of them, showed both groups LH and FSH increased marginally as well.
In the average young man aged 15 – 22, testosterone and E2 concentrations were also seen to change before and after a 10-day oral course of anastrozole at a dosage of 0.5 and 1mg. The results of these studies do suggest that one single dose of .5mg would combat the side effects that are associated with estrogen. One factor that has to be taken into consideration is that to obtain optimal muscle growth, the body does require some estrogen in order to do this. To achieve ‘harder’ and therefore a better ‘quality’ appearance during cutting cycles, body-builders, anecdotally at least, would need lower estrogen levels.
With the increase in levels of testosterone being so high, it is at this point that it needs to be pointed out that Arimidex can be used as a testosterone replacement therapy for men who are suffering from a condition known as Hypogonadism. This is a medical term that describes a lowered function of the gonads which results in less testosterone being produced. The end result of the use of Arimidex in these instances would mean that PCT (post-cycle therapy) would be enhanced and therefore natural testosterone levels would be regained as well as the Hypothalamic-Testicular-Pituitary-Axis, HTPA functioning as it should.
The original manufacturer of Anastrozole – Arimidex is produced by Zeneca Pharmaceuticals – provides users with a pamphlet that indicates that after only 7 consecutive daily doses of 1mg will produce stable blood plasma concentrations. As well as this Arimidex as an aromatase inhibitor is 80% effective. This means that anyone who starts taking the compound a week before cycling will benefit from the full effects of using Arimidex.
However, it is possible to take it for the duration of the cycle, but is this safe to do? From a bodybuilding point of view, lower estrogen levels are a bonus, water retention is reduced as well as any potential for gynecomastia. One factor in favor of using Arimidex is that it is gentle on blood lipids also known as cholesterol and studies have shown that it does not appear to affect them in any adverse manner.
However, as previously stated, lowered estrogen levels may affect cholesterol levels and possibly have adverse immune system effects. For short-term use when taken during an entire cycle and PCT, Arimidex can be used and some experts recommend this. For anyone on long and heavy cycles, then this should be taken as an ancillary compound. This is especially true as Arimidex does not prevent or inhibit the Insulin-like growth factor, IGF which other ancillary compounds tend to do.