Nolvadex Side Effects


Nolvadex is very well tolerated by many, and especially by men. Very rarely are Nolvadex side effects reported by male anabolic steroid using athletes and bodybuilders. The majority of the side effects associated with Nolvadex are found in female breast cancer patients, where many of the listed potential side effects are unseen in males or are far more pronounced in females than males. This is because the action of Nolvadex’s Estrogen antagonist/agonist properties in females affects them very differently than males due to the vast difference in endocrine physiology between the male and female genders. Because females possess naturally higher Estrogen levels necessary for proper female physiological function, the impact of Nolvadex side effects are far more reaching and more pronounced than in males.

The potential Nolvadex side effects among female breast cancer patients includes: hot flashes, vaginal itching, upset stomach, headaches, dizziness, bone and joint pains, and edema. Less common side effects for female breast cancer patients include: cholesterol changes, altered white blood cell count, altered platelet count, skin rashes, endometrial changes, deep vein thrombosis, and pulmonary embolism.

The majority of the above listed Nolvadex side effects are normally never apparent in male users, which compose nearly all of the anabolic steroid users that might elect to utilize Nolvadex for whichever reason.

The Myth of Nolvadex Increasing Progesterone Receptor Sensitivity

It makes sense to cover and dispel this commonly held myth here in the Nolvadex side effects portion of the profile. For a very long time it was misunderstood among the anabolic steroid using community that Nolvadex would bind to and activate Progesterone receptors on breast tissue, resulting in increased potential for gynecomastia during the use of Progestogenic 19-nor compounds (such as Nandrolone and Trenbolone, which are themselves Progestins) due to the misunderstanding that Nolvadex would up-regulate the Progesterone receptors. Many individuals then wrongly and/or mistakenly advised individuals among the anabolic steroid using community to avoid the use of Nolvadex during the use of Nandrolone or Trenbolone even if gynecomastia was developing.

Unfortunately, people did not investigate the origins of this myth and misconception lest they would have noticed the errors in understanding. It is well understood (and thoroughly covered in this profile) that Nolvadex is a mixed Estrogen receptor agonist/antagonist. This is the same for Progesterone receptors as well. In various studies, Nolvadex can and does up-regulate the Progesterone receptors in various tissues throughout the body, such as the endometrium (the uterus) in females. This is a commonly known and well documented effect of Nolvadex in females. This is because the endometrium is naturally very sensitive to Estrogen, and therefore the same would occur with anything that acts as an Estrogen (such as Nolvadex) in said tissues.

This is the first part of the confusion as to this particular myth of this Nolvadex side effect. The second part of the myth and misunderstanding is the fact that in breast tissue, Nolvadex acts as an Estrogen antagonist, meaning it will block the Estrogen receptor from allowing Estrogens to bind to it. This should be common knowledge at this point in the profile. The Progesterone receptor is in fact up-regulated in response to Estrogen. Therefore, when the Estrogen receptor is effectively blocked by Nolvadex in breast tissue, the Progesterone receptor will, as a result, down-regulate.

The problem herein lies in the fact that this does not occur in cancer patients, but it does in normal healthy humans. The origin of this myth, therefore, is that one particular study had demonstrated the fact that Nolvadex expressed up-regulation of the Progesterone receptor in the breast tissue of breast cancer patients[1]. The problem with the myth lies in the interpretation of the study: the subjects in the aforementioned study that experienced Progesterone receptor up-regulation were breast cancer patients, not healthy normal human subjects (and not male subjects either). Hormones and their receptor interactions exhibit drastically different behavior within those afflicted with breast cancers as opposed to normal healthy people. Cancers can cause anomalies in the body whereby the body will begin to exhibit very odd behavior and processes that are not ordinary (and often times the exact opposite) of normal human function, and this is a prime example.

If an individual exhibits gynecomastia as a result of Progestogenic 19-nor use (such as Deca Durabolin or Tren), it is perfectly fine and in fact recommended to utilize Nolvadex in order to mitigate the condition.



Medical References:


[1] Aromatase inhibitors: cellular and molecular effects. Miller WR, Anderson TJ, White S, Larionov A, Murray J, Evans D, Krause A, Dixon JM. J Steroid Biochem Mol Biol. 2005 May;95(1-5):83-9.