MENT Overview, Dosing & Safety | Peptide Database

MENT (Trestolone)

19-Nor Anabolic Steroid | Experimental TRT Alternative

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MENT (7-alpha-methyl-19-nortestosterone), also known as trestolone, is an experimental synthetic anabolic-androgenic steroid that belongs to the 19-nor (nandrolone) family. It was originally developed by the Population Council as a potential male hormonal contraceptive and androgen replacement therapy. MENT is estimated to be roughly 10 times more potent than testosterone on a milligram-per-milligram basis, which allows for effective use at very low doses. Unlike nandrolone, MENT does not cause the characteristic sexual dysfunction ('deca dick') associated with other 19-nor compounds, because it maintains sufficient androgenic activity in the central nervous system and sexual tissues. This property has generated significant interest in MENT as a potential standalone replacement for testosterone -- a compound that could serve as both the anabolic and androgenic base in hormone replacement protocols. MENT aromatizes, but its aromatization product is 7-alpha-methyl-estradiol rather than standard estradiol. This methylated estrogen behaves differently from estradiol in some respects, and aromatase inhibitors like anastrozole have reduced efficacy against it. Estrogen management on MENT is therefore considered more challenging than with testosterone. The acetate ester is the most widely available formulation and has an extremely short half-life of approximately 40 minutes, necessitating daily or twice-daily injections for stable blood levels. Research into longer-acting esters and delivery systems (including subdermal implants) is ongoing. MENT remains an investigational compound with no current FDA approval, though Phase 2 clinical trials for male contraception have been conducted.

MENT binds to the androgen receptor with high affinity, estimated at roughly 10 times the potency of testosterone, driving robust activation of AR-dependent gene transcription pathways responsible for protein synthesis, nitrogen retention, and satellite cell proliferation in skeletal muscle. Its 7-alpha methyl group renders it resistant to 5-alpha reductase, meaning it is not converted to a reduced metabolite in androgen-sensitive tissues the way testosterone is converted to DHT or nandrolone is converted to DHN. MENT itself acts directly on androgen receptors throughout the body, including the brain, prostate, and sexual tissues, which is why it maintains libido and sexual function unlike nandrolone. MENT aromatizes via the aromatase enzyme, but the product is 7-alpha-methyl-estradiol rather than estradiol. This methylated estrogen retains estrogenic activity and binds to estrogen receptors, but conventional aromatase inhibitors (anastrozole, letrozole) have diminished ability to block its formation. The mechanism behind this reduced AI efficacy appears related to the 7-alpha methyl group altering the substrate's interaction with the aromatase active site. MENT powerfully suppresses the hypothalamic-pituitary-gonadal (HPG) axis, reducing LH and FSH to near-undetectable levels at relatively low doses. This profound gonadotropin suppression is the basis for its investigation as a male contraceptive, as it can reduce sperm production to azoospermia or severe oligospermia in most men. Despite its 19-nor classification, MENT does not appear to have the significant progestogenic activity that nandrolone exhibits, though some degree of progesterone receptor interaction has been reported in preclinical studies.

Molecular Data

Research Indications

MENT is being investigated as an alternative to testosterone for androgen replacement. Its high potency allows for low-volume injections, and unlike nandrolone it maintains sexual function without requiring a concurrent testosterone base. Subdermal implant formulations have been studied to provide sustained release over months, potentially offering a more convenient delivery method than testosterone injections.

MENT's primary clinical research focus. Phase 2 trials have demonstrated that MENT, alone or in combination with a progestin, can suppress spermatogenesis to azoospermia or severe oligospermia in the majority of men. The contraceptive effect is reversible upon discontinuation. MENT's advantage over testosterone-based contraceptive approaches is its greater potency and the fact that it does not require 5-alpha reduction for full androgenic activity.

MENT produces significant dose-dependent increases in lean body mass. Due to its potency being roughly 10 times that of testosterone, even low doses (5-10 mg/day) can produce anabolic effects comparable to moderate doses of testosterone. Higher doses (15-25 mg/day) produce substantial muscle growth but with increased side effect burden, particularly estrogenic effects.

Users consistently report rapid and significant strength increases on MENT, often noticeable within the first 1-2 weeks due to the fast-acting acetate ester. Strength gains appear to scale with dose and are accompanied by notable improvements in training recovery.

Unlike nandrolone and trenbolone (other 19-nor compounds), MENT maintains libido and erectile function because it acts directly on androgen receptors in the brain and sexual tissues without being reduced to a weaker metabolite. Many users report enhanced libido on MENT, particularly at lower doses before estrogenic side effects become prominent.

Dosing Protocols

MENT is most commonly available as trestolone acetate for intramuscular or subcutaneous injection. The acetate ester has an extremely short half-life of approximately 40 minutes, which means blood levels rise and fall rapidly. Daily injection is the absolute minimum frequency, and many users prefer twice-daily injections (morning and evening) to maintain more stable blood levels and reduce peak-related side effects. Longer-acting esters (trestolone decanoate, trestolone enanthate) have been discussed in research contexts but are not widely available. Subdermal implant formulations have been studied in clinical trials and could eventually provide sustained multi-month delivery.

TRT Replacement - Low Dose

5-10 mg/day

Daily (or split into 2 injections per day)

Intramuscular or subcutaneous

Moderate Anabolic Protocol

10-15 mg/day

Split into 2 injections per day

Higher Dose - Advanced

15-25 mg/day

Reconstitution Instructions

MENT acetate vial (typically 50-100 mg/mL in MCT or carrier oil)

Insulin syringes (0.5 mL or 1 mL with 27-31 gauge needle) for subcutaneous injection

Alternatively: 1 mL syringes with 25-27 gauge needle for intramuscular injection

Alcohol swabs

Sharps container

1 Wash hands thoroughly and prepare a clean work surface

2 Wipe vial stopper with alcohol swab and allow to dry

3 Draw the prescribed dose into an insulin syringe (volumes are typically very small, 0.05-0.25 mL)

4 Clean injection site with alcohol swab

5 For subcutaneous: pinch skin at abdomen or love handle area, insert needle at 45-degree angle, inject slowly

6 For intramuscular: insert needle at 90-degree angle into deltoid, ventrogluteal, or vastus lateralis

7 Withdraw needle and apply gentle pressure with gauze

8 Dispose of needle in sharps container

9 Repeat daily or twice daily as per protocol

Interactions

What to Expect

Side Effects & Safety

Common Side Effects

Estrogen management difficulty -- 7-alpha-methyl-estradiol is harder to control with conventional aromatase inhibitors

Water retention and bloating, particularly at doses above 10 mg/day

Elevated blood pressure, often linked to water retention and estrogenic load

Mood changes including irritability, emotional sensitivity, or anxiety (frequently estrogen-related)

Profoundly suppressive of the HPG axis -- LH and FSH driven to near-zero even at low doses

Injection frequency burden (daily or twice-daily with acetate ester)

Mild acne and oily skin

Increased appetite

Stop Signs - Discontinue if:

Severe chest pain, tightness, or pressure

Sudden shortness of breath or difficulty breathing at rest

Swelling, warmth, or pain in one leg (potential deep vein thrombosis)

Severe or persistent headaches with visual disturbances

Rapid or significant gynecomastia progression that does not respond to AI adjustment

Signs of stroke: sudden numbness, confusion, trouble speaking, loss of coordination

Persistent severe depression or suicidal ideation

Blood pressure consistently above 160/100 despite management efforts

Contraindications

Prostate cancer (active or history of hormone-sensitive prostate cancer)

Breast cancer in males or females

Pregnancy or potential for pregnancy

Severe hepatic impairment

Polycythemia (hematocrit above 54% at baseline)

Uncontrolled hypertension or severe cardiovascular disease

Uncontrolled heart failure

Known hypersensitivity to trestolone or any formulation components

Quality Checklist

Good Signs

Clear, pale yellow to colorless oil with no visible particles or cloudiness

Proper labeling with concentration (typically 50 or 100 mg/mL), ester type (acetate), and expiration date

Concentration consistent with labeled amount (MENT acetate is typically 50-100 mg/mL)

Intact rubber stopper with no signs of prior puncture

Oil draws smoothly with appropriate viscosity

Third-party lab testing documentation available

Warning Signs

Underground lab product without independent verification or batch testing

Concentration claims above 100 mg/mL (MENT acetate has solubility limitations at higher concentrations)

Vial label with spelling errors, misaligned printing, or unprofessional appearance

Oil appears slightly darker than expected but is otherwise clear

No documentation of carrier oil type

Bad Signs

Cloudy, discolored, or particulate-containing solution (contamination risk)

Crashed product (crystallized steroid visible in vial)

Broken or missing tamper-evident seal on vial

No labeling, incorrect labeling, or missing expiration date

Pain, redness, or swelling at injection site lasting more than 72 hours (potential infection or abscess)

Product sourced without any testing or third-party verification

Frequently Asked Questions

Can MENT work without a testosterone base?

Yes, MENT is one of the few compounds that maintains sexual function and libido without exogenous testosterone, unlike nandrolone or trenbolone. However, some users prefer adding 50-100 mg/week testosterone for the downstream metabolites (DHT, standard estradiol) it provides. MENT solo is viable and increasingly common, particularly at TRT-level doses (5-10 mg/day).

How do I manage MENT's unusual estrogen (7-alpha-methyl-estradiol)?

Conventional aromatase inhibitors have reduced efficacy against 7-alpha-methyl-estradiol, so you'll need higher AI doses than expected or a different strategy. Some users find moderate anastrozole (0.5-1 mg EOD) still provides partial control; others prefer managing water retention and mood through lower MENT doses and close bloodwork monitoring rather than escalating AI use. There's no perfect solution—trial and adjustment is necessary.

What's the best MENT dose for TRT replacement?

MENT at 10-15 mg/day (split into 2 injections) is roughly equivalent to 200-300 mg/week testosterone from a hormonal perspective. Start at 5 mg/day and titrate based on libido, mood, and subjective androgenic effects. Lower doses (5-10 mg) with or without a small testosterone top-up provide an alternative to traditional TRT that some find cleaner, though long-term data is sparse.

Does MENT suppress testosterone more than testosterone itself?

Yes, MENT is profoundly suppressive of the HPG axis even at low doses due to its extreme potency (~10x testosterone). LH and FSH often approach zero. If fertility preservation is a concern, run HCG alongside MENT (500-1000 IU 2-3x per week) to maintain testicular function. This is more critical with MENT than with comparable testosterone doses due to the depth of suppression.

References

Foundational paper characterizing MENT as a candidate male contraceptive. Demonstrated that MENT is approximately 10 times more potent than testosterone for gonadotropin suppression and does not undergo 5-alpha reduction, providing the rationale for its development as a hormonal contraceptive.

Reviewed the pharmacological profile of MENT as both a contraceptive and androgen replacement agent. Confirmed its high potency, resistance to 5-alpha reductase, ability to maintain sexual function, and robust HPG axis suppression. Discussed subdermal implant formulations for sustained delivery.

Clinical pharmacokinetic study comparing subcutaneous and intramuscular delivery of MENT acetate. Found rapid absorption and short half-life by both routes, with peak blood levels within 30-60 minutes. Provided the clinical basis for dosing frequency recommendations.

Phase 2 clinical trial demonstrating that MENT acetate subdermal implants combined with etonogestrel effectively suppressed spermatogenesis in healthy men. The majority of participants achieved azoospermia or severe oligospermia, supporting MENT's potential as a reversible male contraceptive.

Proof-of-concept study evaluating MENT acetate alongside testosterone undecanoate for male contraception. Demonstrated synergistic gonadotropin suppression and high rates of spermatogenic suppression, further validating the clinical development pathway for MENT-based contraceptive regimens.

Related Peptides

HCG helps maintain testicular function and fertility potential during MENT use. MENT is profoundly suppressive of the HPG axis, driving LH and FSH to near-zero. HCG (500-1000 IU 2-3x per week) preserves intratesticular testosterone production, testicular volume, and spermatogenesis potential. Particularly important for those using MENT as a standalone compound without exogenous testosterone.

Aromatase inhibitors have reduced efficacy with MENT because its aromatization product, 7-alpha-methyl-estradiol, is a methylated estrogen that is less effectively blocked by conventional AIs. Anastrozole will still provide some estrogen control but typically not as complete as when managing estrogen from testosterone. Users may need higher AI doses than expected, and some find AIs insufficient at higher MENT doses. Monitor symptoms and bloodwork closely -- standard estradiol assays may not fully capture 7-alpha-methyl-estradiol levels.

While MENT appears to have less progestogenic activity than nandrolone, some users report prolactin-related symptoms at higher doses. Cabergoline (0.25-0.5 mg twice weekly) can be used if bloodwork confirms elevated prolactin. Use only when indicated by symptoms or lab values, not prophylactically.

Unlike nandrolone, MENT does not require a testosterone base to maintain sexual function. However, some users choose to include low-dose testosterone (75-100 mg/week) alongside MENT for the downstream metabolites that testosterone provides (DHT, standard estradiol). Running MENT solo is a viable and increasingly common approach, particularly at TRT-level doses.

MENT is resistant to 5-alpha reductase and is not converted to a more potent androgen by this enzyme. As a result, finasteride has no meaningful interaction with MENT itself. If concurrent testosterone is being used, finasteride will still reduce DHT from that testosterone. Unlike with nandrolone, there is no paradoxical worsening of androgenic side effects when combining finasteride with MENT.

Disclaimer

This information is for educational and research purposes only. Consult a healthcare professional before use.