Description

Nandrolone phenylpropionate (NPP) is an anabolic steroid belonging to the 19-nortestosterone family, a substance that can also be produced in small quantities 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 minimal traces.

From a structural point of view, nandrolone differs from testosterone in that it lacks a carbon atom in position 19. 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 certain specific side effects.

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

Nandrolone is known for its relatively favorable tolerability profile. 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 featureof NPP is its estrogenic conversion, which is approximately six times lower than testosterone and occurs without the direct involvement of the aromatase enzyme. Since the main tissue responsible for estrogenic conversion (adipose tissue) is scarcely involved, effects such as water retention and gynecomastia are rare and usually associated only 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 loss of post-cycle results

• Strengthening of bones, ligaments, and connective tissues

• Improvement of skin regeneration and collagen synthesis

• Reduction of joint pain thanks to increased synovial fluid

• Increase in red blood cells, with improved oxygen transport and greater endurance

• Immune system support (also used in clinical settings)

• 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:

• Decreased natural testosterone production

• Slight increase in fat mass

• Rare cases of gynecomastia

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

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Dosage

• Joint and bone support (elderly individuals): 50–150 mg per week for 5–10 weeks

• Muscle mass increase: 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: twice a week

Nandrolone phenylpropionate has a shorter half-life than other nandrolone esters, making it suitable for shorter mass cycles. A typical cycle lasts 8–10 weeks; longer cycles require the use of hCG to preserve endocrine function. Combination with testosterone is strongly recommended to counteract 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 any of the excipients

• High levels of calcium in the blood

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Storage

• Keep out of reach of children

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

• Store at room temperature

• Do not use after the expiration date