Designed to treat breast cancer and commonly found under the trade name Femera, Letrozole is a potent Aromatase Inhibitor (AI) used by many in performance enhancing circles. Carrying traits similar to Exemestane (Aromasin) and almost identical to Anastrozole (Arimidex), Letrozole is the most potent of the three common forms. Perfect for on-cycle estrogenic anabolic steroid side-effect prevention, while this medication is sometimes used to combat breast cancer when SERM's have failed it is sometimes found in Testosterone Replacement Therapy (TRT) plans. In any case, on-cycle side-effect prevention remains its most common point of use, but this little AI as you can see serves a multitude of purposes.
Although used as a performance enhancing drug, Letrozole is not an anabolic steroid nor will it provide any significant boost in performance; it exists solely as an AI. By its direct function, Letrozole inhibits the aromatase process; an enzyme based reaction that can cause many of the common anabolic steroid related side-effects. Through the aromatase process, a conversion of testosterone to estrogen exists, thereby increasing the total amount of estrogen in the body. By its nature, Letrozole inhibits this process, and further reduces the total amount of estrogen in the body. While labeling Letro, as it is commonly known as an anti-estrogen is a little off-base, it's not that far off. At any rate, of the common AI's, Letrozole will reduce total estrogen more so than any other, with many reports claiming a total reduction of nearly 98%.
Beyond its anti-estrogen related qualities, Letrozole also possesses the ability to significantly stimulate the production of natural testosterone. As you understand, testosterone is produced in the testicles, but before such production can exist the pituitary must release Luteinizing Hormone (LH) and Follicle Stimulating Hormones (FSH) with LH carrying the brunt of responsibility. Without LH and FSH, there is no testosterone production, as these two hormone signal to the testicles to produce more testosterone.
As many anabolic steroids aromatize causing a buildup of estrogen, numerous and some of the most commonly associated side-effects can occur. In-order to combat such issues, responsible use of aromatizing steroids is the first line of defense, but an AI like Letrozole can provide a strong advantage. By inhibiting the aromatase enzyme, the buildup of estrogen cannot occur, and if it cannot occur such related problems cannot manifest. Through use conjoined with your supplemental anabolic steroid plan, side-effects such as Gynecomastia and excess water retention can be avoided. Further, large buildups in estrogen can have a negative impact on blood pressure and cholesterol, and through the use of this AI we are afforded even more protection.
As discussed above, Letrozole can have a very positive effect on natural testosterone production. For this reason, some physicians prescribe this AI in the treatment of low testosterone or for those suffering from Andropause. Some reports have stated such use of Letrozole can increase total testosterone by as much as 50% in some men, but often this is not enough, and at times a meaningless treatment. A 50% increase can be more than welcomed, but an increase of 50% does not necessarily mean you will now be at a suitable level. In most U.S. medical circles, any total testosterone level below 300ng/dl is considered low, and in that light if your total levels are below 150ng/dl Letrozole will not bring you back into a normal range. Further, if the release of LH and FSH are not the reason behind your low testosterone, all the Letrozole in the world won't save you. The only true way to combat low testosterone in a TRT plan is with true and direct exogenous testosterone therapy.
Some performance enhancers, especially in recent years have begun supplementing with AI's like Letro for their Post Cycle Therapy (PCT) needs. The premise is straightforward; Letrozole promotes natural testosterone production that has been suppressed due to anabolic steroid use, and as testosterone recovery is essential to a PCT plan the problem is solved. While Letro will promote testosterone recovery, it is not the best option, and further goes against the overall premise of a PCT plan. While recovering natural testosterone levels is intrinsic to the PCT plan, it is not the primary goal. The primary goal of a PCT plan is to normalize the body, and with Letrozole suppressing estrogen to such a large degree this cannot occur. For PCT purposes, your best course of action is the use of SERM's such as Tamoxifen Citrate (Nolvadex) or Clomiphene Citrate (Clomid) and in many cases with one of these SERM's conjoined with the potent peptide hormone Human Chorionic Gonadotropin (hCG). If you're looking for more, if you really want to protect your gains, the continuation of Human Growth Hormone (HGH) can dramatically help; assuming it was part of your previous on-cycle plan.