Results and Uses of Anastrozole

What is Anastrozole?

Anastrozole is a prescription drug, available in the form of an oral tablet. This tablet is available as the brand name called Arimidex. This drug is anti-cancer hormone therapy and is classified as a non-steroidal aromatase inhibitor. Anastrozole, like letrozole, is a non-steroidal aromatase inhibitor (AI) used to lower circulating oestrogen levels in postmenopausal women with estrogen-responsive breast cancer. It is similar to exemestane, a steroidal AI, but its non-steroidal nature offers significant benefits, such as the absence of steroid-related side effects like weight gain and acne.

Anastrozole Uses

Anastrozole is used in conjunction with other therapies, such as surgery or radiation for the treatment of early breast cancer in postmenopausal women. This drug is also used as first-line therapy for breast cancer that has spread beyond the breast or to other parts of the body in women that have gone through menopause. The drug belongs to the class of drugs called nonsteroidal aromatase inhibitors. This works by reducing the amount of estrogen the body makes. The medication can slow or stop the growth of various types of breast cancer cells which need estrogen to grow.


Before taking Anastrozole talk with your doctor if you are allergic to it or any other medication-related to it. The drug may contain some inactive ingredients which will cause serious allergic reactions or some other serious problems. Before using the drug talk with your doctor if you are having any medical history such as: Kidney disease, liver disease, heart disease, osteoporosis, high blood pressure and blood clots. The drug is primarily prescribed to women during menopause. This drug should not be used during pregnancy if you have not yet reached menopause. When taking this drug and for at least 3 weeks after stopping it, talk to your doctor about using a safe method of birth control (such as latex condoms).

How Anastrozole Works for Bodybuilding

More recently it was discovered that Anastrozole can be used with a high level of success when used by athletes, with bodybuilders having shown the best results. The dose of Anastrozole works by blocking an enzyme known as aromatase. This has the effect of preventing the production of estrogen. When used in combination with steroids, Anastrozole has taken over in popularity from steroids alone and it is now thought to be the most used drug for bodybuilders.
Hormones are chemical substances that are produced by glands in the body, which enter the bloodstream and can cause effects in other parts of the body. For example, the hormone testosterone is made in the testicles and is responsible for male characteristics such as deepening voice and increased body hair. The use of hormone therapy to treat cancer is based on the observation that cancer cell growth can partially depend on hormone binding to receptors on the cancer cell surface.
Hormone therapies can work through methods such as stopping the production of a certain hormone or interfering with hormone binding to the cancer cell receptor. The different types of hormone therapies are categorized by their function and/or the type of hormone that is affected.
Anastrozole is an aromatase inhibitor. This means it blocks the enzyme aromatase (found in the body’s muscle, skin, breast and fat), which is used to convert androgens (hormones produced by the adrenal glands) into estrogens. Tumor cells dependent on estrogens grow less when there is no estrogen.
Note: We strongly encourage you to talk with your health care professional about your specific medical condition and treatments. The information contained in this website is meant to be helpful and educational, but is not a substitute for medical advice.
We often think of testosterone and estrogen as exclusively male (androgen) and female (estrogen) hormones. However, men and women naturally produce both hormones, and a balance between the two is vital for good health in both sexes. 
In men, having too little testosterone or too much estrogen can lead to problems like low sex drive, breast tenderness or enlargement, and erectile dysfunction. The primary sex hormone for men is testosterone, which is made in what are called Leydig cells in the testicles. Men also make a small amount of estradiol, a potent estrogen. 
Estradiol is made directly by the testicles, but the majority comes from the conversion of testosterone into estradiol by the aromatase enzyme. Anastrozole blocks the action of aromatase (called aromatization), which slows down the conversion of testosterone to estradiol. This boosts overall testosterone levels and lowers estradiol. 

Effectiveness of anastrozole in men

There is limited evidence for anastrozole’s effectiveness in men.
In one small study, anastrozole increased testosterone in older men with mild hypogonadism (low T). In another study looking at men with low testosterone and infertility, taking anastrozole led to increased testosterone and increased sperm count in some. 
Although anastrozole may increase testosterone levels, a recent analysis suggests that it doesn’t lead to improvements in sexual function like better erections or higher libido (sex drive). It also doesn’t improve semen quality. Currently, there isn’t sufficient evidence to recommend anastrozole as a routine treatment for low T in clinical practice.
When compared to clomiphene, another off-label treatment for low T, men had significantly higher increases in testosterone than on anastrozole. 
In some cases, a healthcare professional might consider prescribing low-dose anastrozole for men who receive TRT. The reason is that testosterone injections can increase estrogen levels, sometimes leading to unwanted breast growth (gynecomastia) in men. Arimidex and other aromatase inhibitors may reduce estrogen hormone levels in men and potentially treat gynecomastia.


Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.
Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.