Metenolone enanthate

Metenolone enanthate

Clinical data
Trade names	Nibal Injection, Primobolan Depot
Other names	Methenolone enanthate; Metenolone heptanoate; Metenolone 17β-enanthate; NSC-64967; SH-601; SQ-16374; 1-Methyl-4,5α-dihydrotestosterone 17β-heptanoate; 1-Methyl-DHT heptanoate; 1-Methyl-5α-androst-1-en-17β-ol-3-one 17β-heptanoate
Routes of administration	Intramuscular injection
Drug class	Androgen; Anabolic steroid; Androgen ester
Legal status
Legal status	US: Schedule III
Pharmacokinetic data
Elimination half-life	IM Tooltip Intramuscular injection: 10.5 days [1]
Identifiers
IUPAC name [(5S,8R,9S,10S,13S,14S,17S)-1,10,13-trimethyl-3-oxo-4,5,6,7,8,9,11,12,14,15,16,17-dodecahydrocyclopenta[a]phenanthren-17-yl] heptanoate
CAS Number	303-42-4  Y
PubChem CID	248271
ChemSpider	217360  Y
UNII	0SPD480WFH
CompTox Dashboard (EPA)	DTXSID7046754
ECHA InfoCard	100.005.584
Chemical and physical data
Formula	C27H42O3
Molar mass	414.630 g·mol−1
3D model (JSmol)	Interactive image
SMILES O=C2\C=C(\C)[C@@]3([C@H]1CC[C@@]4([C@@H](OC(=O)CCCCCC)CC[C@H]4[C@@H]1CC[C@H]3C2)C)C
InChI InChI=1S/C27H42O3/c1-5-6-7-8-9-25(29)30-24-13-12-22-21-11-10-19-17-20(28)16-18(2)27(19,4)23(21)14-15-26(22,24)3/h16,19,21-24H,5-15,17H2,1-4H3/t19-,21-,22-,23-,24-,26-,27-/m0/s1 Y Key:TXUICONDJPYNPY-FRXWOFFRSA-N Y
NY  (what is this?)    (verify)

Metenolone enanthate, or methenolone enanthate, sold under the brand names Primobolan Depot and Nibal Injection, is an androgen and anabolic steroid (AAS) medication which is used mainly in the treatment of anemia due to bone marrow failure. ^{[2] [3] [4] [5] [6] [7]} It is given by injection into muscle. ^[6] Although it was widely used in the past, the drug has mostly been discontinued and hence is now mostly only available on the black market. ^{[5] [6] [3]} A related drug, metenolone acetate, is taken by mouth. ^[6]

Side effects of metenolone enanthate include symptoms of masculinization like acne, increased hair growth, voice changes, and increased sexual desire. ^[6] The drug is a synthetic androgen and anabolic steroid and hence is an agonist of the androgen receptor (AR), the biological target of androgens like testosterone and dihydrotestosterone (DHT). ^{[6] [8]} It has moderate anabolic effects and weak androgenic effects, as well as no estrogenic effects or risk of liver damage. ^{[6] [8]} Metenolone enanthate is a metenolone ester and a long-lasting prodrug of metenolone in the body. ^[6]

Metenolone enanthate was introduced for medical use in 1962. ^[6] In addition to its medical use, metenolone enanthate is used to improve physique and performance. ^[6] The drug is a controlled substance in many countries and so non-medical use is generally illicit. ^[6] It remains marketed for medical use only in a few countries, such as Spain and Turkey. ^{[5] [6]}

Medical uses

Metenolone enanthate has been studied in the treatment of breast cancer. ^{[9] [10]}

Side effects

See also: Anabolic steroid § Adverse effects

Pharmacology

Pharmacodynamics

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Androgenic vs. anabolic activity ratio
of androgens/anabolic steroids

Medication	Ratioa
Testosterone	~1:1
Androstanolone (DHT)	~1:1
Methyltestosterone	~1:1
Methandriol	~1:1
Fluoxymesterone	1:1–1:15
Metandienone	1:1–1:8
Drostanolone	1:3–1:4
Metenolone	1:2–1:30
Oxymetholone	1:2–1:9
Oxandrolone	1:3–1:13
Stanozolol	1:1–1:30
Nandrolone	1:3–1:16
Ethylestrenol	1:2–1:19
Norethandrolone	1:1–1:20
Notes: In rodents. Footnotes:a = Ratio of androgenic to anabolic activity. Sources: See template.

As a derivative of DHT, metenolone, the active form of metenolone enanthate, is not aromatized, and so has no propensity for producing estrogenic side effects like gynecomastia. ^[6] As an AAS, metenolone enanthate is antigonadotropic and can suppress the hypothalamic–pituitary–gonadal axis and produce reversible hypogonadism and infertility. ^{[6] [11]}

Pharmacokinetics

The biological half-life of metenolone enanthate is reported to be about 10.5 days by intramuscular injection. ^[1]

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Parenteral durations of androgens/anabolic steroids

Medication	Form	Major brand names	Duration
Testosterone	Aqueous suspension	Andronaq, Sterotate, Virosterone	2–3 days
Testosterone propionate	Oil solution	Androteston, Perandren, Testoviron	3–4 days
Testosterone phenylpropionate	Oil solution	Testolent	8 days
Testosterone isobutyrate	Aqueous suspension	Agovirin Depot, Perandren M	14 days
Mixed testosterone esters a	Oil solution	Triolandren	10–20 days
Mixed testosterone esters b	Oil solution	Testosid Depot	14–20 days
Testosterone enanthate	Oil solution	Delatestryl	14–28 days
Testosterone cypionate	Oil solution	Depovirin	14–28 days
Mixed testosterone esters c	Oil solution	Sustanon 250	28 days
Testosterone undecanoate	Oil solution	Aveed, Nebido	100 days
Testosterone buciclate d	Aqueous suspension	20 Aet-1, CDB-1781e	90–120 days
Nandrolone phenylpropionate	Oil solution	Durabolin	10 days
Nandrolone decanoate	Oil solution	Deca Durabolin	21–28 days
Methandriol	Aqueous suspension	Notandron, Protandren	8 days
Methandriol bisenanthoyl acetate	Oil solution	Notandron Depot	16 days
Metenolone acetate	Oil solution	Primobolan	3 days
Metenolone enanthate	Oil solution	Primobolan Depot	14 days
Note: All are via i.m. injection. Footnotes:a = TP, TV, and TUe. b = TP and TKL. c = TP, TPP, TiCa, and TD. d = Studied but never marketed. e = Developmental code names. Sources: See template.

Chemistry

See also: List of androgens/anabolic steroids and List of androgen esters

Metenolone enanthate, or metenolone 17β-enanthate, is a synthetic androstane steroid and a derivative of DHT. ^{[2] [3] [6]} It is the C17β enanthate (heptanoate) ester of metenolone, which itself is 1-methyl-δ¹-4,5α-dihydrotestosterone (1-methyl-δ¹-DHT) or 1-methyl-5α-androst-1-en-17β-ol-3-one. ^{[2] [3] [6]}

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Structural properties of major anabolic steroid esters

Anabolic steroid	Structure	Ester				Relative mol. weight	Relative AAS contentb	Durationc
		Position	Moiety	Type	Lengtha
Boldenone undecylenate		C17β	Undecylenic acid	Straight-chain fatty acid	11	1.58	0.63	Long
Drostanolone propionate		C17β	Propanoic acid	Straight-chain fatty acid	3	1.18	0.84	Short
Metenolone acetate		C17β	Ethanoic acid	Straight-chain fatty acid	2	1.14	0.88	Short
Metenolone enanthate		C17β	Heptanoic acid	Straight-chain fatty acid	7	1.37	0.73	Long
Nandrolone decanoate		C17β	Decanoic acid	Straight-chain fatty acid	10	1.56	0.64	Long
Nandrolone phenylpropionate		C17β	Phenylpropanoic acid	Aromatic fatty acid	– (~6–7)	1.48	0.67	Long
Trenbolone acetate		C17β	Ethanoic acid	Straight-chain fatty acid	2	1.16	0.87	Short
Trenbolone enanthate d		C17β	Heptanoic acid	Straight-chain fatty acid	7	1.41	0.71	Long
Footnotes:a = Length of ester in carbon atoms for straight-chain fatty acids or approximate length of ester in carbon atoms for aromatic fatty acids. b = Relative androgen/anabolic steroid content by weight (i.e., relative androgenic/anabolic potency). c = Duration by intramuscular or subcutaneous injection in oil solution. d = Never marketed. Sources: See individual articles.

History

Metenolone enanthate was introduced for medical use in 1962 in the United States under the brand name Nibal Depot. ^[6] It was soon discontinued in the United States and was marketed instead in Europe in the 1960s and 1970s under the brand name Primobolan Depot. ^[6]

Society and culture

Generic names

Methenolone enanthate is the USAN Tooltip United States Adopted Name of metenolone enanthate, and methenolone is the BAN Tooltip British Approved Name of its active form, metenolone. ^{[2] [3] [4] [5]} Conversely, metenolone is the INN Tooltip International Nonproprietary Name of metenolone. ^{[2] [3] [4] [5]}

Brand names

Metenolone enanthate is or has been marketed under the brand names Nibal Injection and Primobolan Depot. ^{[2] [3] [6] [5]}

Availability

Metenolone enanthate is marketed in Spain and Turkey. ^{[5] [6]}

Doping in sports

See also: List of doping in sport cases § Metenolone esters

There are known cases of doping in sports with metenolone enanthate by professional athletes.

References

1. Westreich LM (2011). "Anabolic-Androgenic Steroids". In Ruiz P, Strain EC (eds.). Lowinson and Ruiz's Substance Abuse: A Comprehensive Textbook. Lippincott Williams & Wilkins. pp. 358–. ISBN   978-1-60547-277-5.
2. Elks J (14 November 2014). The Dictionary of Drugs: Chemical Data: Chemical Data, Structures and Bibliographies. Springer. pp. 784–. ISBN   978-1-4757-2085-3.
3. Index Nominum 2000: International Drug Directory. Taylor & Francis. 2000. pp. 659–661. ISBN   978-3-88763-075-1.
4. Morton IK, Hall JM (6 December 2012). Concise Dictionary of Pharmacological Agents: Properties and Synonyms. Springer Science & Business Media. pp. 178–. ISBN   978-94-011-4439-1.
5. "List of Androgens and anabolic steroids".
6. William Llewellyn (2011). Anabolics. Molecular Nutrition Llc. pp. 633–. ISBN   978-0-9828280-1-4.
7. Handelsman DJ (25 February 2015). "Androgen Physiology, Pharmacology, and Abuse". In Jameson JL, De Groot LJ (eds.). Endocrinology: Adult and Pediatric E-Book. Elsevier Health Sciences. pp. 2388–. ISBN   978-0-323-32195-2.
8. Kicman AT (2008). "Pharmacology of anabolic steroids". Br. J. Pharmacol. 154 (3): 502–21. doi:10.1038/bjp.2008.165. PMC   2439524 . PMID   18500378.
9. Kennedy BJ, Yarbro JW (February 1968). "Effect of methenolone enanthate (NSC-64967) in advanced cancer of the breast". Cancer. 21 (2): 197–201. doi: 10.1002/1097-0142(196802)21:2<197::AID-CNCR2820210207>3.0.CO;2-R . PMID   4952912.
10. Notter G (December 1975). "Treatment of disseminated carcinoma of the breast by metenolone enanthate". Acta Radiologica. 14 (6): 545–551. doi: 10.3109/02841867509132696 . PMID   1224996.
11. van Breda E, Keizer HA, Kuipers H, Wolffenbuttel BH (Apr 2003). "Androgenic anabolic steroid use and severe hypothalamic-pituitary dysfunction: a case study". Int J Sports Med. 24 (3): 195–196. doi:10.1055/s-2003-39089. PMID   12740738. S2CID   260166539.

External links

• Primobolan Depot (methenolone enanthate) - William Llewellyn's Anabolic.org Archived 2019-06-29 at the Wayback Machine