Equipoise 300 is the popularly referenced brand name for the veterinary injectable steroid boldenone undecylenate. Specifically it is a derivative of testosterone, which exhibits strong anabolic and moderately androgenic properties. The undecylenate ester greatly extends the activity of the drug (the undecylenate ester is only one carbon atom longer than decanoate), so that clinically injections would need to be repeated every three or four weeks. In veterinary medicine Equipoise is most commonly used on horses, exhibiting a pronounced effect on lean bodyweight, appetite and general disposition of the animal. This compound is also said to shows a marked ability for increasing red blood cell production, although there should be no confusion that this is an effect characteristic of newly all anabolic/androgenic steroids. The favourable properties of this drug are greatly appreciated by athletes, Equipoise being a very popular injectable in recent years. It is considered by many to be a stronger, slightly more androgenic Deca-Durabolin. It is generally cheaper, and could replace Deca in most cycles without greatly changing the end result.
The side effects associated with Equipoise are generally mild. The structure of boldenone does allow it to convert into estrogen, but it does not have an extremely high affinity to do so. To try and quantify this we can look toward aromatization studies, which suggest that its rate of estrogen conversion should be roughly half that of testosterone’s. The tendency to develop a noticeable amount of water retention with this drug would therefore be slightly higher than that with Deca-Durabolin (with an estimated 20°/a conversion), but much less than what would be expected with a stronger agent such as Testosterone. While one does still have a chance of encountering an estrogen related side effect as such when using this substance, it is not a common problem when taken at a moderate dosage level. Gynecomastia might theoretically become a concern, but is usually only heaved of with very sensitive individuals or (again) those venturing high in dosage. Should estrogenic effects become troublesome, the addition of proper acilliary would be highly recommended making the cycle more tolerable. An antiaromatase such as Cytadren® or Arimidex would be stronger options, however probably not indicated with a mild drug as such.