Arimidex Background and History

A relatively new drug, Anastrozole was only developed in the early 1990s before being released in 1995 under the brand name Arimidex by AstraZeneca.

Arimidex belongs to a group of drugs known as Aromatase Inhibitors (AIs) and is used in a variety of medical conditions.

Estrogen is synthesized by an enzyme known as aromatase. By blocking the actions of the receptors or by preventing the estrogen being synthesized entirely, AIs can help to lower the amount of estrogen in the body.

Certain cancer cells require estrogen in order to grow and spread so by slashing the supply, it can help to prevent the disease from progressing. The Arimidex drug has proven to be particularly useful in treating breast cancer in post-menopausal women who have undergone surgery, as well as metastatic breast disease in both pre and post-menopausal women.

Anastrozole (Arimidex) is considered such a ground-breaking drug that it was included on the World Health Organization’s Model List of Essential Medicines in 2015.

However, although there are a number of therapeutic applications for Arimidex, the drug is often utilized for off-label use in the bodybuilding community.

When taking anabolic steroids, estrogen can cause some very undesirable effects on the male body, including gynecomastia and water retention. The only way to eliminate these is by reducing the amount of estrogen in the body. This can be achieved by using an AI such as Arimidex.

Using stacking

Arimidex isn’t a drug that’s taken on its own for the purposes of enhancing performance. It’s used alongside anabolic steroids in order to reduce the estrogen related side effects.

It can be used either as a preventative measure or because early signs of gynecomastia have appeared. Arimidex is used in a stack with anabolic steroids and normally continues for the duration of the cycle.

How it is administered

Arimidex is normally administered orally, either via tablets or less commonly, a liquid. The latter is normally only available from research labs so most users opt for the more convenient tablets.


The dosage of Arimidex depends on whether it’s being taken as a preventative measure or because the early symptoms of gynecomastia have started to manifest.

When taken for the purposes of prevention, it’s normal to start with 0.5mg every other day, increasing to 1mg every other day if needed.

If there are concerns that gynecomastia is starting to develop, up to 1mg every day can be taken. For the vast majority, this dose will be sufficient to eliminate any estrogen-related problems. This can be maintained until the symptoms have been eradicated, at which time the dosage can be dropped to every other day for the duration of your cycle.

In a small number of users, AIs such as Arimidex will not be able to combat the effects of estrogen complications such as gynecomastia.

Half-life info

Arimidex has a half life of 46 hours which means that when it’s being dosed daily, the plasma levels will soon start to build up.

Positive effects

Arimidex is not normally taken for the purposes of performance enhancement but more to control the effects of estrogen caused by anabolic steroids.

These can include both gynecomastia and bloating, both of which Arimidex can help to combat. The latter can cause hypertension and the drug can provide protection against this too.

Using Arimidex can also provide a much harder and drier appearance and it’s common for users to increase their dose in the 48 hours prior to a competition.

Potential side effects

Arimidex is not a drug which is renowned for having particularly severe side effects and in many people, it is tolerated well.

Problems can arise if the dosing guide is not adhered to because having too little estrogen in the body can be problematic. A lack of estrogen can result in fatigue, low mood and an inability to sustain erections.

Some of the side effects which might be experienced at the correct dose include headaches, raised blood pressure, pain in the joints and hot flashes. In rare cases, depression and nausea may occur.

Studies have shown that in the general population bone density can be reduced by taking Arimidex but this isn’t such a problem for bodybuilders because steroids typically help to increase bone minerals. This counterbalances the potential effect.

Fatigue is a common issue when taking Arimidex for therapeutic purposes but again, isn’t normally an effect that bodybuilders experience. The only exception is during a cutting cycle when calorific intake is low.

picture of 2 arimidex pills

However, the single biggest problem among the Arimidex side effects is cholesterol. When combined with anabolic steroids, the drug can cause the healthy HDL cholesterol to decrease by as much as 25%. For this reason, it’s essential to follow a heart-friendly lifestyle including a low fat diet and regular cardiovascular exercise.

Some experts suggest that the negative effects of Arimidex on cholesterol can be offset somewhat by adding 10mg of Nolvadex to the stack.


Although the Arimidex medication is generally considered to be a relatively safe drug to take, there are some instances where its use is not recommended. This includes anyone with a history of any of the following:

  • High cholesterol
  • Decreased bone density
  • Decreased calcification in the bones
  • Problems with the blood flow to the heart muscle

In addition, it’s not been proven as safe to use for women who are pregnant or breastfeeding.

Is it safe for women to use?

The role of estrogen in male and female bodybuilders is very different because in a woman’s body, the hormone plays much more of an important role. Therefore, it’s not a good idea to block estrogen in a female in the same way as you would in a man.

For this reason, Arimidex is taken primarily by men to combat the unwanted effects of estrogen, a problem that women generally don’t have to deal with.

However, women may take Arimidex for very short periods, particularly prior to competitions, when they’re seeking a much drier and hard look. But unlike Arimidex for men, use of the drug must be limited in women and taken at a low dose.

Will PCT be required?

Within bodybuilding, Arimidex is utilized as a drug that reduces the unwanted effects of anabolic steroids, specifically the aromatizing process.

Although Arimidex has been shown to play a role in increasing the body’s own natural production of testosterone, the fact that it will be taken alongside an anabolic steroid in a cycle means that PCT will be required.

There have been some suggestions that Arimidex can even be used as part of an effective PCT program but it clashes with Nolvadex, a drug which many believe is essential following a cycle. Therefore, even though Arimidex has a role in increasing testosterone it’s not normally included in PCT.

Typical cost

Although Arimidex cannot be bought legally over the counter, it’s still a drug which is widely available.

It’s easy to buy Arimidex online, both from pharmaceutical sources and from underground labs in tablet form. If you want liquid Arimidex, you’ll need to source a Research Chemical Lab (RCL) which sells it, but that’s not as difficult as it sounds.

The quality of the drug can be a big influence on the price you pay. Pharmaceutical grade Arimidex is more expensive than the research grade equivalent, with underground labs being the cheapest of all. Consider carefully where you decide to buy Arimidex online from; although the tablets won’t present much danger, if they’re poorly made you could be under or over dosing without realizing, or could be paying too much for a weaker compound.

As a rough rule of thumb, the Arimidex cost is around $6-11 per 1mg tablet where there are no minimum restrictions on the size of the order. Other suppliers who set a limit on the minimum quantity they are prepared to sell – typically $200-400 per purchase – can offer Arimidex from as little as $2 per 1mg pill.

Legality of purchase and its usage in the US

Unlike anabolic steroids, Arimidex is not classified as a controlled substance in the US. This means that it’s not subject to the same severe penalties which are passed for both distribution and personal use.

However, it is necessary to obtain a prescription from a physician in order to get Arimidex. This can only be supplied for the treatment of a medical condition; it is not legal for a physician to write a prescription for Arimidex to supplement a bodybuilding cycle.

If you don’t have a prescription for Arimidex for a legitimate medical condition, you may still find sources to be able to purchase it from, but you will be breaking the law.

While the above is true, there is one area of exception in US law which exists: purchases for the purposes of research. It’s possible to buy pharmaceutical grade Arimidex but this must be for research. In the unlikely event of being questioned by the authorities, you would need to be able to demonstrate a genuine research project in order to avoid legal action being taken against you.