by Bill Roberts
- Anastrozole (Arimidex) is the aromatase inhibitor of choice.
The drug is appropriately used when using substantial amounts
of aromatizing steroids, or when one is prone to gynecomastia
and using moderate amounts of such steroids. Arimidex does
not have the side effects of aminoglutethimide (Cytadren) and
can achieve a high degree of estrogen blockade, much more so
than Cytadren. It is possible to reduce
estrogen too much with Arimidex, and for this reason blood tests,
or less preferably salivary tests, should be taken after the first
week of use to determine if the dosing is correct.
As an aromatase inhibitor, Arimidex's
mechanism of action -- blocking conversion of aromatizable steroids
to estrogen -- is in contrast to the mechanism of action of anti-estrogens
such as clomiphene (Clomid) or tamoxifen
(Nolvadex), which block estrogen receptors in some tissues,
and activate estrogen receptors in others. During a cycle, if
using Arimidex, there is generally no need to use Clomid as well,
but (as mentioned in the section on Clomid)
there may still be benefits to doing so.
Arimidex is quite expensive, costing
approximately $9 per milligram. With moderate doses of testosterone
0.5 mg/day is usually sufficient and in some cases may be too