Anabolic Steroids/Hormones
Testosterone Enanthate
Also called Test E · TE · Test Enth
Testosterone enanthate is prescribed for diagnosed testosterone deficiency. Bodybuilders also use it hoping for muscle and strength gains. TRT and nonmedical use involve different amounts, goals and risks.
Dosage & duration
Adult medical regimens for distinct uses and preparations.
IM TRT · Endocrine Society starting examples
Published example · product-specific- Dose
- 75–100 mg per injection weekly, or 150–200 mg per injection every 2 weeks
- How often
- Into muscle: weekly or every 2 weeks, matching the chosen regimen
- How long
- Ongoing when indicated; no fixed cycle
Published guideline examples, adjusted to symptoms and measured testosterone. Some vial labels give a broader range; follow the prescribed product and plan.
Xyosted · US product label
Product label- Dose
- Start: 75 mg. Available adjusted doses: 50, 75 or 100 mg per injection
- How often
- Once weekly, under the abdominal skin
- How long
- Ongoing replacement; no fixed label course
A different route and device. The label bases adjustment on trough blood testing after 6 weeks; this page’s IM curve does not model the Xyosted autoinjector.
Sources: 4
Amounts are testosterone-enanthate mg, not mL or pen/vial total content. TRT is monitored treatment; these medical examples do not define a bodybuilding cycle or recovery date.
One dose · modeled timing
Why injections overlap
100% = the model’s peak, not the dose left or a blood-test result.
About this curve
Some testosterone from an earlier injection remains when another dose is added. The model helps show how spacing changes that overlap.
- Compare equal totals
- Keep the total amount over the same period constant when comparing injection frequency.
- Separate timing from symptoms
- The curve shows a modeled contribution from injections, not energy, libido or a total-testosterone blood test.
Published adult model for testosterone enanthate injected into muscle. It excludes testosterone made by the body. The highest point is shown as 100% to make the timing easier to compare. This is not a target blood-test level.
Model assumptions and sourcesWhy people use testosterone enanthate
Bodybuilders seek more muscle and strength; people prescribed TRT want relief from symptoms of confirmed testosterone deficiency. Those are different goals. Human studies support muscle and strength effects at higher exposure, but do not establish a safe bodybuilding cycle.
Some people also report changes in libido, mood, skin and water retention. Feeling more driven in the gym is not a complete picture of how someone is responding.
Enanthate or cypionate?
Both release testosterone. Availability, injection comfort and the routine often matter more to readers than the ester name. Some people report more post-injection pain after changing products or esters. That does not show that every enanthate product hurts or that cypionate is always better tolerated.
Check the actual product: vial concentrations vary, and Xyosted is a specific under-the-skin autoinjector with different instructions from the intramuscular vial modeled here.
Once weekly or split injections?
Fewer injections are convenient; more frequent ones mean more preparation. To compare timing in the plotter, keep the weekly total equal. Dividing it reduces the model’s peak-to-trough swing, but a smoother line does not guarantee better mood or fewer side effects.
The curve shows testosterone contributed by the injections, excluding natural production. Its ng/dL values are not a total-testosterone blood-test prediction.
What needs follow-up?
Blood pressure, red blood cells, acne, fluid retention and breast symptoms matter even when training is going well. Testosterone can suppress natural hormone and sperm production. Discuss fertility plans before treatment; stopping does not guarantee quick recovery. For prescribed TRT, review recurring symptoms and consistently timed blood tests with the prescriber.
Model details: Testosterone Enanthate
How to read this chart
This is a study-based example of how testosterone levels change over time. Try different doses or timing to compare the curves.
The calculation uses the same assumptions for everyone. It can't predict your own blood levels or tell you what dose to take.
Only testosterone from the entered doses is shown. Your body's own production isn't included, so this isn't your total blood level.
Study setup and sources
testosterone: exogenous contribution in serum (ng/dL).
The body's own testosterone is excluded. This is the contribution from entered doses, not the total blood level.
Fixed reference profile: Ten adult men with hypogonadism already receiving IM testosterone enanthate; adult model reanalysis of the 2015 cohort. Testosterone enanthate 200 mg/mL in sesame oil (West-Ward), as studied in the IM reference cohort.; Intramuscular. Fixed reference weight: 90.35 kg.
Changing dose or schedule explores a scenario; it does not personalize the reference profile or establish a studied regimen.
Input dose basis: Nominal testosterone enanthate mg
Source exposure scope: The adult IM source cohort received a 200 mg study injection on existing treatment. Other schedules are simulations under fixed linear parameters, not additional observed regimens.
Adult IM testosterone enanthate: injected-drug model component
vogiatzi-2023-enanthate-im-component · version 1
- Published adult fixed-effect parameters; no individual random effects or pediatric allometric scaling.
- Zero initial exogenous amount and no endogenous testosterone contribution. Prior treatment is included only when its dose events are entered.
- Nominal testosterone enanthate dose enters the model directly; no additional ester-mass or bioavailability multiplier.
- Model structure
- One compartment with absorption
- Apparent clearance (CL/F)
- 50.569 L/hour
- Apparent central volume (Vc/F)
- 13755.8 L
- Absorption rate (ka)
- 0.0831 /hour
- Input mass conversion
- 1 mg modelled mass per mg entered
- This mathematical injected-drug component is not a measured fraction of an individual blood sample or a prediction of total testosterone.
- The small source cohort had prior treatment and variable endogenous testosterone. Clinical effects, endogenous recovery and fertility are not modeled.
- These IM parameters do not describe subcutaneous autoinjectors, other formulations or pediatric patients.
- Changing a simulated dose or interval does not establish treatment suitability, a testing date or an expected change in adverse effects.
- Vogiatzi et al. 2023 — adult IM population model
Adult one-compartment model; pediatric simulations in the paper are not implemented.
- Vogiatzi et al. — supplementary Table 3 and Figures 7–8
Full-precision IM fixed effects: Ka 0.0831/h, V 13755.8 L, CL 50.569 L/h. Figure 8 includes different initial endogenous levels, excluded from this component.
- Kaminetsky et al. 2015 — underlying clinical cohort
The IM sesame-oil reference arm is separate from the subcutaneous autoinjector arms; observed total-testosterone endpoints are not isolated-dose peaks.
Safety and interaction notes Read the limitations and discuss clinical questions with a professional
- Aromatizes
- Yes
- DHT derivative
- No
Common questions
Is 200 mg per week automatically TRT?
No fixed milligram amount determines whether treatment is appropriate replacement. The diagnosis, prescribed formulation, symptoms and measured testosterone all matter. A plotting default is not a prescription.
Does injecting twice weekly work better than once weekly?
Splitting the same weekly amount can reduce the modeled rise and fall, but it adds injections and does not guarantee better symptoms or fewer adverse effects. The useful comparison keeps the total amount and product consistent.
How long do people stay on testosterone enanthate?
TRT may be ongoing when the underlying deficiency persists and treatment remains appropriate. Nonmedical users report fixed courses, including the twelve-week example above, but that does not establish a safe duration or predictable recovery.
Can testosterone enanthate affect fertility?
Yes. Testosterone treatment can suppress sperm production. Discuss fertility goals before starting or changing treatment rather than assuming that a short course will preserve fertility.
Will the plot match my testosterone blood test?
It models only testosterone contributed by the entered intramuscular doses. It excludes the body’s own production and individual variation, so it is not a total-testosterone laboratory prediction.
Is enanthate better for bulking than cypionate?
Both deliver testosterone. The ester changes release timing; it does not create a special bulking effect. Bodybuilding discussions focus on strength and size, but reports of water retention, mood and injection comfort differ. A personal preference is not proof that one ester builds more muscle.
Sources Labels, studies and notes behind this guide
Catalog evidence: Other human research. This describes the type of evidence, not a clinical review of every claim.
Summary and fact source checks: 2026-10-07. This records source checking, not medical review of the whole page.
Notes on the quick facts
- TRT goal
- Clinical assessment combines symptoms with repeated low morning testosterone results; low energy alone does not establish a diagnosis.
- Physique goal
- Higher-than-replacement amounts have increased muscle size and strength in human research, particularly with lifting. That is a different goal from TRT.
- Timing trade-off
- Splitting the same total amount changes the rise and fall between doses. More injections are not a guarantee of fewer symptoms or adverse effects.
- 1. Endocrine Society 2018 — testosterone therapy guideline
Table 5 gives 75–100 mg/week or 150–200 mg every two weeks for IM enanthate/cypionate. Diagnosis requires symptoms plus consistently low testosterone; monitoring includes symptoms, testosterone and hematocrit. These are guideline regimens, not the broader vial-label range.
- 2. Testosterone enanthate IM vial — US DailyMed label
Current full label checked. Adult hypogonadism wording gives 50–400 mg every 2–4 weeks, with dose and duration individualized. That broad label range is not substituted for the separately attributed guideline examples. Supports slow oil-depot absorption, blood-pressure, blood-count, abuse and reproductive cautions.
- 3. Bhasin et al. 1996 — testosterone enanthate and strength training
Original randomized trial: 43 men without testosterone deficiency; 600 mg IM weekly for ten weeks, with or without standardized strength training. Supports muscle/strength effects above replacement exposure; it does not establish a safe nonmedical regimen, long-term outcomes or expected personal gains.
- 4. Xyosted — US prescribing information
Sections 2.1–2.3: 75 mg once weekly under the abdominal skin initially; 50/75/100 mg strengths. Adjustment uses trough total testosterone after six weeks and six weeks after a change. The autoinjector is not for IM administration; no fixed total course length is specified.
- 5. Vogiatzi et al. 2023 — testosterone enanthate population model
Full text checked via Europe PMC. Adult IM parameters came from 10 men receiving 200 mg; endogenous testosterone and pediatric extrapolation are separate limitations.
- 6. Kaminetsky et al. 2015 — SC and IM testosterone enanthate study
Full text checked via Europe PMC. Small open-label study; IM reference cohort was already receiving replacement, unlike the washed-out SC groups.
- 7. Vogiatzi et al. 2023 — adult IM population model
Adult one-compartment model; pediatric simulations in the paper are not implemented.
- 8. Vogiatzi et al. — supplementary Table 3 and Figures 7–8
Full-precision IM fixed effects: Ka 0.0831/h, V 13755.8 L, CL 50.569 L/h. Figure 8 includes different initial endogenous levels, excluded from this component.
- 9. Kaminetsky et al. 2015 — underlying clinical cohort
The IM sesame-oil reference arm is separate from the subcutaneous autoinjector arms; observed total-testosterone endpoints are not isolated-dose peaks.
Keep reading
Related compounds and examples
Related compounds
Testosterone Cypionate
Testosterone cypionate for TRT and reported bodybuilding use: goals, sourced doses, weekly versus split injections, blood-test timing and side effects.
Testosterone Propionate
Testosterone propionate appeals to people who want testosterone with a shorter release profile. Bodybuilders seek muscle and strength; the everyday trade-off is frequent injections rather than a special kind of testosterone.
Testosterone Undecanoate (Castor Oil)
Long-acting testosterone undecanoate is used for TRT when fewer injection appointments are a priority. Nebido and Aveed can last many weeks between injections, but their doses and starting schedules differ.
Protocols featuring Testosterone Enanthate
Beginner Testosterone Enanthate (12 weeks)
The canonical first cycle: 500 mg Test E per week (250 mg 2×/week) for 12 weeks. The most-cited textbook beginner cycle.
Test E + Deca with NPP Frontload (20 weeks)
Long cycle using NPP for a fast kickstart while Deca reaches steady state.
Test E + Dianabol Bulking Kickstart (12 weeks)
Classic bulking base of Test E with 4 weeks of Dianabol to front-load mass.