Description:

Nandrolone Phenylpropionate is the injectable form of the anabolic steroid Nandrolone. This drug shares similar properties with Decanoate Nandrolone. The main difference between these two formulations is the speed at which Nandrolone is released into the bloodstream. While Decanoate provides about three weeks of Nandrolone release at the injection site, Phenylpropionate offers just one week. Therefore, in clinical settings, Decanoate can be injected every two or three weeks, whereas Phenylpropionate requires weekly injections. However, these two drugs are essentially interchangeable. Like Decanoate, Phenylpropionate is valuable for athletes and bodybuilders seeking to increase muscle strength and lean muscle mass, with no significant estrogenic or androgenic side effects.

History:

Nandrolone Phenylpropionate first appeared in 1957. Soon after, it became a prescription drug marketed by the international pharmaceutical giant Organon (now Merck/MSD) under the brand name Nandrolone Phenylpropionate. Initially introduced in the United States, it was used for pre-and post-operative sperm quality retention, osteoporosis, advanced breast cancer, recovery period or disease-induced weight loss, geriatric ailments (general weakness and frailty), burns, severe trauma, ulcers, anemia, and as an adjunct therapy for children with growth retardation. In the 1970s, the FDA began modifying the uses of this drug, and its applications quickly diminished. Over time, the drug was primarily used for treating advanced metastatic breast cancer and as an adjunct therapy for post-menopausal osteoporosis in the elderly.

Nandrolone Phenylpropionate remained a focus of Organon's marketing efforts for less than a decade. When Decanoate Nandrolone was introduced in the 1960s, the shorter-acting Phenylpropionate, although still available, began to decline. At that time, Organon had not yet given up on Phenylpropionate, partly because its therapeutic uses varied slightly by country, thus maintaining a profitable market for some time. Due to the expanding market for anabolic steroids during the 1970s and 1980s, other drug manufacturers began to take notice, leading many pharmaceutical companies to start producing their own Nandrolone Phenylpropionate. However, today, this drug is almost nonexistent. The current owners of Organon (Merck/MSD) will discontinue the sale of Nandrolone Phenylpropionate, and its production (as a branded product) will end.

Specifications Provided:

Nandrolone Phenylpropionate is available in some human pharmaceutical markets. The composition and dosage may vary by country and manufacturer, but it typically contains 25 mg/mL or 50 mg/mL of steroid dissolved in oil.

Structural Characteristics:

Nandrolone Phenylpropionate is a modified form of Nandrolone, where the carboxylic acid ester (phenylpropionate) has been attached to the 17-β hydroxyl group. Esterified steroids are less polar than free steroids and are absorbed slower from the area of injection. Once in the bloodstream, the ester is removed to yield free (active) Nandrolone. Esterified steroids are designed to extend the therapeutic effect window after administration, allowing less frequent injections compared to administering free (unesterified) steroids. Nandrolone Phenylpropionate reaches peak Nandrolone release 24-48 hours after deep intramuscular injection, and declines to near baseline levels within a week.

Side Effects (Estrogenic):

Nandrolone has a low rate of estrogen conversion, estimated to be about 20% of that of testosterone. This is because although the liver can convert Nandrolone to estradiol, in other more active sites of steroid aromatization, such as adipose tissue, Nandrolone exhibits much less estrogenic activity than testosterone. However, elevated estrogen levels due to high doses can still be noticeable and may cause side effects such as increased water retention, body fat increase, and gynecomastia. Anti-estrogens such as Clomiphene or Tamoxifen may be necessary to prevent the appearance of estrogenic side effects. Aromatase inhibitors like Anastrozole, which prevent the synthesis of estrogen, can more effectively control estrogen levels. However, compared to anti-estrogens, aromatase inhibitors can be quite expensive and may also have a negative impact on blood lipids.

It's notable that Nandrolone exhibits some progestogenic activity in the body. Despite being a C-19 steroid, the removal of this group to yield 19-nor compounds produces hormones with a significantly greater binding affinity for their corresponding receptors. Due to this feature, many non-19-nor anabolic steroids display some affinity for progesterone receptors. Progestogenic side effects are similar to those of estrogen, including a negative feedback suppression of testosterone production and an increased rate of fat storage. Progesterone also enhances the stimulatory effect of estrogen on mammary tissue growth. There seems to be a strong synergistic effect between these two hormones, so gynecomastia could potentially occur under the influence of progesterone even without excessive estrogen levels. Using anti-estrogens that inhibit the components of estrogen is usually sufficient to mitigate gynecomastia caused by Nandrolone.

Side Effects (Androgenic):

Although classified as an anabolic steroid, this substance can still cause androgenic side effects, especially at higher doses. These side effects may include oily skin, acne, and episodes of body/facial hair growth. Anabolic/androgenic steroids can also exacerbate male-pattern hair loss. Women are warned of the potential virilizing effects of anabolic/androgenic steroids. These may include deepening of the voice, menstrual irregularities, changes in skin texture, facial hair growth, and clitoral enlargement. Nandrolone is a steroid with relatively low androgenic activity compared to its tissue-building actions, making the threshold for androgenic side effects quite high compared to androgenic drugs such as testosterone, methyltestosterone, or fluoxymesterone. It's also important to note that due to its mild androgenic nature and ability to suppress endogenous testosterone, Nandrolone can easily disrupt libido in males when not used with another androgen.

Note that in androgen-responsive target tissues such as the skin, scalp, and prostate, the relative androgenicity of Nandrolone is reduced by its reduction to dihydronandrolone (DHN). The 5-alpha reductase enzyme is primarily responsible for this metabolism. Using 5-alpha reductase inhibitors such as Finasteride or Dutasteride disrupts this site-specific action of Nandrolone, thereby significantly increasing the tendency for Nandrolone to produce androgenic side effects. If low androgenicity is desired, avoid using reductase inhibitors with Nandrolone.

Side Effects (Hepatotoxicity):

Nandrolone is not c-17α alkylated and does not exhibit hepatotoxic effects. Therefore, hepatotoxicity is unlikely to occur.

Side Effects (Cardiovascular):

Anabolic/androgenic steroids can have deleterious effects on serum cholesterol. This includes a tendency to lower HDL (good) cholesterol values and increase LDL (bad) cholesterol values, which may shift the HDL to LDL balance and increase the risk of arteriosclerosis. The relative impact of anabolic/androgenic steroids on serum lipids depends on the dose, method of administration (oral vs. injection), the type of steroid (aromatizable or non-aromatizable), and level of resistance to hepatic metabolism. A study administering 600mg of Decanoate Nandrolone per week for 10 weeks showed a 26% decrease in HDL cholesterol levels. This suppression is slightly higher than the suppression reported with the same dosage of Testosterone Cypionate, consistent with early research findings, which indicate that Decanoate Nandrolone has a more negative effect on the HDL/LDL ratio than Testosterone Propionate. The impact on serum lipids by Nandrolone is significantly less than that of c-17α alkylated agents. Anabolic/androgenic steroids can also adversely affect blood pressure and triglycerides, reduce endothelial relaxation, and lead to left ventricular hypertrophy, all potentially increasing the risk of cardiovascular disease and myocardial infarction.

To help reduce cardiovascular strain, it is advised to maintain an active cardiovascular exercise program and to minimize the intake of saturated fats, cholesterol, and simple carbohydrates during AAS use. It is also recommended to supplement with fish oil (4 grams per day) and a natural cholesterol/antioxidant formula such as Lipid Stabil or a similar product.

Side Effects (Testosterone Suppression):

When taken at doses sufficient to promote muscle gain, all anabolic/androgenic steroids are expected to suppress endogenous testosterone production. Studies injecting 100mg of Nandrolone Phenylpropionate have shown that a single injection can rapidly suppress serum testicular hormones. Testosterone levels drop to 30% of initial levels by the third day after administration and remain suppressed for about 13 days. Frequent use can significantly extend the window for the recovery of endogenous hormones. It is believed that Nandrolone's progestational activity significantly favors the suppression of testosterone synthesis during treatment. Without intervention from testosterone-stimulating substances, testosterone levels are expected to return to normal within 2-6 months after the drug ceases. Please note that hypogonadal states can develop secondary to steroid abuse and require medical intervention.

Usage (Male):

For general anabolic effects, early prescription guidelines recommended a dose of 25-50 mg per week for a duration of 12 weeks. For physique or performance enhancement purposes, common doses range from 200-400mg per week, in cycles of 8 to 12 weeks. This level is sufficient for most users to see measurable gains in lean muscle mass and strength. Note that due to the rapid action of the phenylpropionate ester, the weekly dose is often split into two applications.

Usage (Female):

For general anabolic effects, early prescription guidelines recommended a dose of 25-50 mg per week for a duration of 12 weeks. When used for physique or performance enhancement purposes, a common dose is 50mg per week (administered in a single weekly injection) for 4 to 6 weeks. Higher doses or longer durations of use are not recommended due to the potential for virilizing side effects. Although only mildly androgenic, women occasionally face virilization symptoms when taking this compound. If virilizing side effects appear, Nandrolone Phenylpropionate should be discontinued immediately to prevent permanent adverse effects.

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