There are some chemicals available that can be incorporated into a post cycle therapy depending upon the needs of the athlete. A SERM (Selective Estrogen Receptor Modulator) like Clomid (Clomiphene Citrate) or Nolvadex (Tamoxifen Citrate) should ideally always be incorporated into the schedule. Before these are administered, the testosterone levels need to be brought to normal.
The leydig cells in the testes need to be stimulated by the Luteinizing Hormone (LH) to produce testosterone on their own. LH needs to be produced by the pituitary gland and the pituitary, in turn, needs to be stimulated by the hypothalamus to do that. But the hypothalamus will not stimulate the pituitary as long as there are excess levels of estrogen in the blood stream. This is why another hormone called the HCG needs to be introduced into the body.
The HCG, or the Human Chorionic Gonadotropin hormone, is produced in the human body by the fertilized egg in a pregnant woman. However, this hormone acts like the LH and can stimulate the leydig cells to generate testosterone. The HCG should, however, be used only as minimally as possible – just enough to bring the testes to start producing testosterone on their own again. The HCG can also be used by athletes who suffer testicular atrophy during their steroid cycles.
The time period which HCG can survive in the human body after being injected is around 3 days. So it should be administered every alternate day for as long as the testes do not start producing testosterone on their own.
After the body is prepared this way, the SERM therapy can be started. If the cycle contained the human growth hormone (HGH), then it needs to be continued in the same manner in the post cycle therapy. This hormone also makes the body retain the gains that were achieved during the cycle.
Coming back to the SERM therapy, it is done to stop the estrogen from inhibiting the pituitary and the hypothalamus from the production of testosterone. The Clomid is actually a medicine that is supposed to boost ovulation in women. But this drug attaches itself to the estrogen receptors inside the pituitary and the hypothalamus. These two glands sense the estrogen level in the blood through these receptors, and according to that, they either start or stop the production of testosterone to maintain homeostasis. When the Clomid molecules attach themselves to these receptors, the glands cannot sense the estrogen.
Nolvadex is another SERM that blocks estrogen, and also works as good as Clomid. In fact, as per some studies, Nolvadex acts best when coupled with HCG. This is for the fact that if HCG doses are too high, Nolvadex blocks the estrogen arising from aromatization, and does not let the leydig cells to become desensitized. This helps in the better release of testosterone. Some people are also of the opinion that it is best to use Nolvadex along with Clomid because that gives the ultimate synergistic effect.
Anyway, the levels of testosterone are low in the body as it is. The glands are blocked from sensing the high levels of estrogen now due to the SERM. This is seen as low testosterone levels in the blood. The pituitary and hypothalamus then signal start of the production of testosterone to the testes. Clomid and Nolvadex are both available in tablet and liquid form. Nolvadex is also used to treat cancerous tissue which is sensitive to estrogen, like breast cancer. Using too much of HCG for a long period of time may cause the leydig cells in the testes to get desensitized. This will not be good for the body. Also, HCG greatly aromatizes into estrogen, so taking higher doses of this hormone should always be coupled with anti-estrogen. That will help prevent conditions like gynecomastia.
High levels of HCG may also cause the production of progesterone in the testes. To prevent this, any aromatase inhibitor like Letrozole or Arimidex can be used. But if any such inhibitor is used, then Nolvadex should not be included in the post cycle therapy plan. This is because Nolvadex directly counteracts the actions of these inhibitors, especially Arimidex, and vice versa. If Nolvadex has to be used, then Aromasin should be the aromatase inhibitor of choice, since Aromasin does not react with Nolvadex in any manner.
Apart from not interfering with Nolvadex, Aromasin is also known to be able to help in the production of testosterone, as well as negatively affect cholesterol levels. This makes it an ideal choice for the post cycle therapy. Cycling between anti-estrogens is always good for consistently keeping the levels of estrogen low in the bloodstream.