Provibol is a synthetic, orally effective androgen which does not have any anabolic characteristics. The active ingredient present in Provibol is Mesterolone.Provibol is used in school medicine to ease or cure disturbances eased by a deficiency of male sex hormones. Many athletes, for this reason, often use Mesterolone at the end of a steroid treatment in order to increase the reduced testosterone production. This however is not a good idea since Provibol has no effect on the body’s own testosterone production but-as mentioned in the beginning-only reduces or completely eliminates the dysfunctions caused by the testosterone deficiency.These are in particular impotence which is mostly caused by an androgen deficiency that can occur after the discontinuance of steroids, and infertility which manifests itself in a reduced sperm count and a reduced sperm quality. Provibol is therefore taken during a steroid administration or after discontinuing the use of the steroids, to eliminate a possible impotency or a reduced sexual interest. This, however does not contribute to the maintainance of strength and muscle mass after the treatment. There are other better suited compounds for this (see HCG and Clomid). For this reason Provibol is unfortunately cunsidered by many to be a useless and unnecessary compound.You should be aware that Provibol is also an estrogen antagonist which prevents the aromatization of steroids. Unlike the antiestrogen Tamoxifen which only blocks the estrogen receptors, Provibol already prevents the aromatizing of steroids. Therefore gynecomastia and increased water retention are successfully blocked. Since Provibol strongly suppresses the forming of estrogens no rebound effect occurs after discontinuation of use of the compound as is the case with, for example, Tamoxifen where an aromatization of the steroids is not prevented. One can say that Tamoxifen cures the problem of aromatization at its root while Tamoxifen simply cures the symptoms. For this reason male athletes should prefer Provibol to Tamoxifen.With Provibol the athlete obtains more muscle hardness since the androgen level is increased and the estrogen concentration remains low. This, in particular, is noted positively during the preparation for a competition when used in combination with a diet. Female athletes who naturally have a higher estrogen level often supplement their steroid intake with Provibol resulting in an increased muscle hardness. In the past it was common for bodybuilders to take a daily dose of one 25 mg tablet over several weeks, sometimes even months, in order to appear hard all year round.This was especially important for athletes appearances at guest performances, seminars and photo sessions. Since Provibol is very effective male athletes usually need only 50 mg/day which means that the athlete usually takes one 25 mg tablet in the morning and another 25 mg tablet in the evening. In some cases one 25 mg tablet per day is sufficient. When combining Provibol with Tamoxifen (50 mg Provibol/day and 20 mg Tamoxifen/day) this will lead to an almost complete suppression of estrogen.