Methenolone enanthate (Primobolan) - the active ingredient of the drug, which appeared in the 1960s thanks to German scientists. At the time, German scientists have been conducting many studies, in which the state invested a lot of money, so that athletes could properly represent their country in various competitions. As it’s well known, the Germans do everything for centuries to come, and Primobolan is no exception to this, because this injectable drug has been popular among bodybuilders and athletes to this day.

Chemical structure

Methenolone is a dihydrotestosterone derivative. It is characterized by one additional connection between carbons one and two, which helps to stabilize the 3-keto group and increase anabolic performance of a steroid, as well by the addition of 1-methyl group that protects a steroid against metabolism in the liver. Primobolan uses methenolone with an ester of carboxylic acid (acetic acid), added to 17-beta hydroxyl group, which protects the drug from oxidation when taken peroraly. Studies have shown that methenolone is an effective oral anabolic either in acetate form or in unesterified form.


  • Anabolic activity - 88% of testosterone
  • Androgenic activity - 44% of testosterone
  • Aromatization (conversion into estrogen) - None
  • Toxicity to the liver – low
  • Type - orally (pills) and injection
  • Duration - 4-6 hours of pills; 10-14 days of injections
  • Detection time - up to 100 days (pills), 6 months (injections)


  • Weak anabolic effect with minor androgenic effect
  • At a dosage of more than 500 mg a week anabolic effect increases several times, which raises Primobolan to the similar level as some steroids of the average action level.
  • Methenolone enanthate is not converted into estrogen, thus avoiding the development of gynecomastia.
  • Characterized by a weak rollback phenomenon
  • Minimal risk of side effects
  • The level of cholesterol and blood pressure remains within normal limits while using Primobolan.
  • Primobolan can be considered one of the safest anabolic steroids available on the market at present time.

Side effects

Primobolan slightly reduces production of testosterone. Its inhibitory impact is weaker than of testosterone and nandrolone. Researches show that the cycle of Primobolan in a dose of 40 mg (orally) suppresses level of testosterone by an average of 50%. A significant reduction of the production of endogenous testosterone is observed only during long courses with high doses of the drug. In these cases, the use of gonadotropin is required during the course, otherwise testicular atrophy may develop.

Due to low androgenic effect Primobolan doesn’t cause hair loss. In most cases, methenolone causes side effects such as aggression, agitation, insomnia, and the rise of liver enzymes if large doses are used.

Dosages and Uses 

  • The course of Primobolan is best suited for the course of cutting to preserve muscles and obtain body relief.
  • Soft effect of the drug requires a long course (up to 8 weeks), but with an increase of the duration of the course of Primobolan, the risk of side effects increases.
  • Oral dosage of Primobolan - 50-100 mg per day. In 2-3 days after the end of the course, post-cycle therapy begins.
  • Dosage of Primobolan depot - 400 mg, once a week. 3 weeks after the last injection post-cycle therapy begins.

Consulting with a doctor is required before the course to eliminate contradictions.

Cycles (Cycles) 

Given the rather weak anabolic effect of methenolone (its ability to increase the weight is little less than nandrolone’s), it is often combined with other drugs.

Course №1

The cycle is designed for athletes who care very much about their health, and try to avoid side effects if possible. The drug has a high price.

Duration: 8 weeks.

Dosage: 350-400 mg of Primobolan per week + 45 mg of oxandrolone daily.

Effect: around 4 kg (8 lbs) of quality muscle mass and the absence of side effects.

Course №2

An interesting variation of cycle for the athletes with little experience in the usage of pharmacology. For those who do not want to take more serious anabolic steroids, and want to prepare their body for more difficult courses.

Duration: 6-8 weeks.

Dosage: 450-650 mg of Primobolan per week + 35-40 mg methandrostenolone daily.

Effect: progress in strength and mass with minimum side effects.

Course №3

The course is designed for experienced pharmacology ‘users’.

Duration: 8 weeks.

Dosage: Primobolan (350-400 mg per week) + testosterone propionate (95 mg every other day) + trenbolone acetate (350-400 mg per week).

Effect: rapid increase of high-quality muscle mass with minimal fluid retention.