Weekly or split?

Splitting the same weekly amount usually gives smaller ups and downs in a testosterone model. It also means more injections. A smoother line does not automatically mean you will feel better.

Compare equal weekly totals first. Repeating the full amount more often changes the dose as well as the timing.

Try a timing comparison Treatment dose context

Keep the weekly total in view

One entry

100 mg

100 mg / week Same total

Split entries

50 mg50 mg

100 mg / week Same total

Repeating the full amount

100 mg100 mg

200 mg / week Double the total

Illustrative arithmetic, not a prescribed schedule. The blocks show input amounts, not blood levels.

Common treatment intervals, with dose context

The Endocrine Society guideline gives 75–100 mg intramuscularly each week, or 150–200 mg every two weeks, as starting examples for testosterone enanthate or cypionate in men with diagnosed deficiency. These are ongoing replacement-treatment examples, not cycle plans. Product, route and follow-up determine an individual prescription. Guideline, Table 5

Some users ask whether twice-weekly or daily schedules would work better for them. Interest in those intervals does not establish that everyone needs them. Keep the weekly total fixed when comparing timing with a prescriber.

Change one variable at a time

Compare A fair frequency comparisonA different-dose comparison
Amount over one week Keep the same total Total also changes
Input size Divide the total across more entries Repeat the original full amount more often
Question answered How does timing affect overlap? What happens when exposure increases too?
Interpretation Peak and trough can be compared Frequency alone cannot explain the difference

A simple arithmetic example

For an illustrative 100 mg weekly total, one 100 mg entry and two 50 mg entries have the same total. Two 100 mg entries double it. This is arithmetic for an existing schedule, not a personal prescription.

Even with equal totals, “Monday and Thursday” does not produce two identical intervals: one is three days, the other four. A calendar model can show that difference; a repeated interval of exactly 3.5 days answers a slightly different question.

What peak and trough describe

The peak is the highest modeled value during the comparison period; the trough is the low point between repeated inputs. A peak-to-trough ratio describes fluctuation, not average exposure or toxicity. A high, nearly flat curve can have a small ratio while still representing substantial exposure.

For depot injections, absorption spreads each input over time. That is why a real concentration peak need not occur at the instant of injection. In a small human cypionate study, peak total-testosterone values occurred across days 2–5 under the regimen studied. Nankin, 1987

Steady state still has peaks and troughs

Steady state means the same dosing pattern produces a repeating pattern of concentrations. It does not mean the line becomes horizontal. In a simple first-order system, each effective half-life closes half of the remaining gap to the eventual pattern: after four half-lives the approach is about 94%, and after five about 97%.

That calculation assumes fixed linear rates. A multi-stage depot, a changed interval or a different model can make a single half-life rule incomplete. Show enough of the timeline to see whether the pattern is still changing.

What a smoother plot cannot decide

It cannot predict an individual’s mood, estradiol, hematocrit or symptom response. More frequent injections also change the practical burden. Treatment decisions therefore include the product’s instructions, tolerability, adherence and appropriately timed bloodwork.

For testosterone, the model may display only the contribution from entered doses. That excludes endogenous production and must not be matched directly to a total-testosterone laboratory range. Read the methodology before comparing numbers.

Try the comparison in the plotter

A useful modeling exercise

  1. Duplicate the same scenario

    Keep the compound, model, route and total amount unchanged.

  2. Change only the spacing

    Divide the input appropriately when adding events.

  3. Use the same time window

    Compare later repeating intervals as well as the first week.

  4. Read all the outputs

    Look at peak, trough and overall exposure; do not choose by smoothness alone.

A saved comparison is a helpful discussion aid for a prescriber. It is not an instruction to alter a prescription.

Sources and model notes

Checked October 12, 2026. The Endocrine Society guideline provides the replacement examples above. Nankin’s cypionate study measured total testosterone in men; it is not the same output as the plotter’s injected-drug component. The opening figure is exact arithmetic and has no concentration or symptom scale. The four-/five-half-life percentages describe a simple linear accumulation rule, not a product-specific treatment deadline.