Known, unknown, and estimated
- Known: accurately entered injection events and timestamped observations.
- Known: the FDA label reports an approximately eight-day intramuscular half-life for testosterone cypionate.
- Unknown: exact hormone concentration, clinical response, and lab interpretation from a consumer log alone.
- Estimate: modeled remaining levels based on a population value and logged timing.
How this page competes in the TRT SERP
The live United States Google results for “TRT tracker app” include dedicated app listings, TRTracker, MyTRT, TRT Plus, and community discussions. Most emphasize injections, symptoms, and labs. The opportunity is a precise record-keeping page that clearly distinguishes records, laboratory measurements, and estimates.
The minimum useful TRT timeline
Injection history
Formulation, amount, unit, route, date, time, site, and supply record.
Schedule history
Planned, completed, delayed, skipped, and changed events remain distinct.
Observation log
Symptoms and notes are timestamped observations, not diagnoses.
Lab context
Record draw dates and source documents without automated interpretation.
Why formulation matters
“Testosterone” is not a sufficiently precise record. Cypionate, enanthate, gels, pellets, and other formulations have different administration and pharmacokinetic contexts. The current testosterone cypionate label's approximately eight-day half-life applies to intramuscular administration and should not be silently generalized to every formulation or route.
What estimated curves are good for
A curve can make the assumptions behind a schedule visible and help explain why repeated events accumulate in a model. It cannot predict an individual's laboratory result or establish a medically appropriate schedule.
Primary sources: FDA Depo-Testosterone prescribing information and Halflife App Store listing.
Keep the complete record in one place
Halflife - Peptide & GLP-1 Log organizes logs, schedules, vial inventory, injection sites, symptoms, and clearly labeled model estimates on iPhone.
Download Halflife - Peptide & GLP-1 Log