Description

Nandrolone phenylpropionate (NPP) is an anabolic steroid belonging to the 19-nortestosterone family, a substance that can also be produced in small amounts naturally by the human body under certain conditions, such as during intense physical activity or pregnancy. Its main metabolite, 19-norandrosterone, is normally present in urine only in trace amounts.

Structurally, nandrolone differs from testosterone in the absence of the 19th carbon atom. This modification gives the compound a partially progestogenic nature and results in significantly lower androgenic activity than testosterone. However, interaction with progesterone receptors may be responsible for some specific side effects.

testosterone, which is converted to the potent dihydrotestosterone (DHT) via the enzyme 5-alpha reductase, nandrolone phenylpropionate Unlike is converted to dihydronandrolone, a much weaker androgen. This makes NPP a more tolerable option for men with prostate sensitivity.

Nandrolone is known for its relatively favorable tolerability profile. Its low androgenic activity reduces the likelihood of side effects such as acne, baldness, and excessive body hair growth, which typically only occur when recommended dosages are exceeded.

Another distinctive aspect of NPP is its estrogenic conversion, which is approximately six times lower than that of testosterone and occurs without the direct involvement of the aromatase enzyme. Since the primary tissue responsible for estrogenic conversion (adipose tissue) is poorly involved, effects such as water retention and gynecomastia are rare and usually only associated with very high dosages.

Thanks to these characteristics, nandrolone phenylpropionate is one of the most popular anabolic steroids for increasing muscle mass with minimal “rollback” after the cycle.

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Effects

• Marked muscle growth with reduced post-cycle loss of results

• Strengthening of bones, ligaments and connective tissues

• Improved skin regeneration and collagen synthesis

• Reduction of joint pain thanks to increased synovial fluid

• Increased red blood cells, with better oxygen transport and greater resistance

• Immune system support (also used clinically)

• Conversion to estradiol without aromatase involvement

• Improved intestinal absorption of amino acids and nutrients

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Side effects

Nandrolone phenylpropionate (NPP) has progestogenic activity: approximately 20% of the substance can bind to progestin receptors, potentially increasing prolactin levels and reducing gonadotropin secretion. This can lead to:

• Reduction of natural testosterone production

• Slight increase in fat mass

• Rare cases of gynecomastia

Other possible side effects include increased blood pressure, abdominal pain, irritability, headache, and depressed mood. Less common side effects include back pain and gynecomastia.

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Dosage

• Joint and bone support (elderly subjects): 50–150 mg weekly for 5–10 weeks

• Muscle gain: 200–800 mg per week

• Average dose: approximately 400 mg of nandrolone per week, often combined with 500 mg of testosterone

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Profile

• Half-life: 2–4 days

• Frequency of administration: 2 times a week

Nandrolone phenylpropionate has a shorter half-life than other nandrolone esters, making it suitable for shorter bulking cycles. A typical cycle lasts 8–10 weeks; longer cycles require the use of hCG to preserve endocrine function. Combining it with testosterone is strongly recommended to counteract the progestogenic effects and prevent decreased libido, erectile dysfunction, and depression.

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Pharmaceutical form

• Oily solution for intramuscular injection

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Contraindications

• Pregnancy

• Known or suspected prostate or breast cancer

• Breastfeeding

• Hypersensitivity to the active substance or to the excipients

• High blood calcium levels

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Conservation

• Keep out of reach of children

• Store in a cool, dry place, away from direct sunlight

• Store at room temperature

• Do not use beyond the expiration date