Half-life reference / Library model input
HCG half-life
The PinPoint library stores 33 hours (1.375 days) for HCG. This is the input behind the arithmetic below, not a measurement of your levels or how long an effect lasts.
DailyMed chorionic gonadotropin prescribing information provides product context; the library stores a 33-hour tracking reference.
Library snapshot, 2026-10-05: CompoundLibrary.swift:552, halfLifeHours: 33. Read the cited reference.
Reading this particular reference
HCG illustrates why a label citation and a numerical model input should be read separately. The library source note identifies labeled product details but does not state that the cited passage establishes the stored 33-hour scalar. Treat that figure as the library tracking reference. HCG amounts may be recorded in IU, while this page expresses only percentages. A normalized decay percentage supplies no conversion between IU, mass, and volume.
No numerical half-life range is stated in the library source note. The library lists subcutaneous, intramuscular for tracking. A listed route is not proof that every input was measured through that route. The linked reference and its study context matter when interpreting the stored number.
HCG decay table
Starting at an arbitrary 100%, each elapsed half-life divides the remaining modeled amount by two. The calculation is 100 × 2 raised to the power of minus elapsed hours divided by 33. It describes a single contribution with no additional entries. The percentages are not percentages of benefit, receptor activity, or symptom relief.
| Half-lives | Hours | Days | Remaining (rounded) |
|---|---|---|---|
| 0 | 0 | 0 | 100.0% |
| 1 | 33 | 1.375 | 50.0% |
| 2 | 66 | 2.75 | 25.0% |
| 3 | 99 | 4.125 | 12.5% |
| 4 | 132 | 5.5 | 6.3% |
What the listed schedules mean mathematically
The library labels are Every other day; Three times weekly; Twice weekly. They describe available tracking patterns, not instructions. In an equal-input model, the limiting peak accumulation ratio is 1 ÷ (1 − 2 raised to minus interval divided by half-life). It compares a repeated pattern with one instantaneous input and assumes the same interval continues indefinitely.
- Every other day, if evenly spaced: 48 hours between entries; 36.49% of one contribution remains at that marker; limiting accumulation ratio 1.574.
- Three times weekly: no unique fixed interval is specified, so no accumulation ratio is assigned.
- Twice weekly: no unique fixed interval is specified, so no accumulation ratio is assigned.
About five half-lives here is 165 hours, or 6.875 days. Under the same linear assumptions, that is approximately the approach to steady state. Changing amounts, missed entries, irregular spacing and absorption change the pattern. The calculation does not decide when to start, stop, or change anything.
From a reference curve to a dose history
PinPoint’s Home curve models your levels between doses from published half-life data. Drag to scrub modeled values at any timestamp, or preview 30 days of a dose pattern. Log injections with compound, dose, site, and pain level, and backfill past doses so the history is complete from day one.
The graph on this page is simpler: it isolates exponential elimination so you can inspect the arithmetic. PinPoint’s modeled curves are mathematical visualizations of published population averages and do not account for individual variation. A modeled amount is not a laboratory concentration.
Explore dose logging in PinPoint or compare library half-life inputs.
Questions, answered
Is the half-life of HCG the same for everyone?
No. Half-life varies with the person, formulation and study context. No numerical half-life range is stated in the library source note. The stored number is a reference input, not a personal measurement.
How long until HCG clears?
With the stored 33-hour scalar, five half-lives take 165 hours (6.875 days), leaving 3.125% of one modeled starting contribution. Exponential decay never reaches exactly zero. This is not a detection window, a washout instruction, or proof that effects have ended.
What does steady state mean?
For unchanged, equally spaced inputs in a linear model, steady state means the pattern repeats from one interval to the next. About five half-lives gives roughly 97% of the limiting pattern. Peaks and troughs still occur; steady state does not mean a flat line or a recommended regimen.
PinPoint is a tracking and unit-conversion tool, not a medical device. Modeled levels are mathematical illustrations, not blood tests or individual predictions. Medical decisions belong with your healthcare provider.