Boldenone is an anabolic steroid evolved for veterinary use, broadly speaking for treatment of horses. It isn't indicated for use in human beings within the US and is only to be had via veterinary clinics.
The activity of boldenone is mainly anabolic, with a low androgenic potency. The drug is commonly used in doping within bodybuilding, even though this use is illegal. If intended to assist in bodybuilding, the drug is taken as part of a steroid stack of other anabolic steroids, usually with a potent androgen like testosterone as the 'base' of the stack. Boldenone is an androgen that differs from 17b-testosterone (17b-T) by only one double bond at the 1-position, and the removal of the methyl group protecting the 17-OH group allows it to be orally active.
Boldenone is a steroid hormone which has androgenic activity. Androgens bind to the androgen receptor, which regulates gene transcription.