What it is

A 19-nortestosterone derivative. One of the oldest and most widely used injectables. Deca-Durabolin is the slow-release version (decanoate ester); NPP is the fast-release version (phenylpropionate ester). Originally developed to treat anaemia, osteoporosis, and muscle-wasting conditions.

What it does

Promotes significant lean muscle growth with less water retention than Dianabol. Known for improving joint health and recovery through increased collagen synthesis. Slower, steadier gains than testosterone alone. Increases nitrogen retention and red blood cell production.

Typical dosages

200-400mg per week is commonly reported for both Deca and NPP. Often run for 12-16 weeks (Deca) or 8-12 weeks (NPP) due to ester length differences. Should always be run with a testosterone base at equal or higher dose. This is not a recommendation; it is what is commonly reported.

These figures reflect commonly reported usage in harm reduction communities. They are not recommendations. There is no safe dose of anabolic steroids for non-medical use. Start low and monitor your health through blood work.

Side effects

Severe suppression of natural testosterone production (more so than testosterone alone)
Erectile dysfunction ('Deca dick') due to impact on progesterone and prolactin
Water retention (less than Dianabol but still significant)
Elevated blood pressure
Negative impact on cholesterol (HDL/LDL)
Depression and anxiety, particularly post-cycle
Progesterone-related gynecomastia
Reduced libido

Specific risks

Recovery: suppresses natural testosterone far more heavily than testosterone alone. PCT recovery is notably harder and longer. The decanoate ester has a very long half-life, meaning suppression continues long after the last injection
Sexual dysfunction: 'Deca dick' is a well-documented issue caused by the compound's impact on progesterone and prolactin pathways. Can persist for weeks or months after stopping
Mental health: depression and anxiety are commonly reported, particularly during the transition off nandrolone. Users should monitor their mental state closely
Cardiovascular: places significant strain on lipids and blood pressure, comparable to other compounds in this class

What to watch for

Erectile dysfunction or loss of libido (early sign of prolactin/progesterone issues)
Persistent low mood or anxiety (particularly after dose changes or stopping)
Significant water retention or blood pressure increases
Nipple sensitivity or discharge (can indicate elevated prolactin)
Blood work showing suppressed LH/FSH many weeks after stopping

Other compounds

Testosterone

Lower/Moderate Risk

The base of almost every steroid cycle. Testosterone is the primary male sex hormone and the most commonly used anabolic steroid.

Trenbolone

Extreme Risk

One of the most powerful and dangerous steroids in common use. Extremely potent but with a severe side effect profile that makes it unsuitable for most users.

Anavar (Oxandrolone)