Enclomiphene half-life and steady state
10 h modelled half-life, peaking 2 h after a dose. What that means for how long it lasts, how much it builds up, and when bloodwork is worth drawing.
- Also known as
- Androxal, Enclomifene, NF-1010
- Class
- Ancillaries — AIs and SERMs
- Modelled half-life
- 10 h
- Time to peak
- 2 h
- Formulation
- Oral
- Cleared per dosing interval
- 81% gone, 19% still present after 24 h
- Time to steady state
- ~2.1 days (about five half-lives)
- Accumulation at that cadence
- 1.23× a single dose
- Peak-to-trough at steady state
- 4.44×
- Regulatory status
- Not FDA approved (NDA submitted as Androxal — pending). Compounding pharmacy sourced in US.
- Monitoring panel
- Total T, Free T, LH, FSH, E2, Semen analysis (if fertility is goal), every 6-8 weeks when adjusting.
- Storage
- Room temperature and dry, in the original container with whatever desiccant came in it, out of light.
- Once opened
- Unchanged once opened, as long as it stays dry.
- What ruins it
- Humidity is the real enemy — a bathroom cabinet is the worst place in the house for these.
- Handling caveat
- General handling practice for this formulation. Your supplier’s own insert or COA overrides anything here.
Enclomiphene's ten-hour half-life is the number that explains why it exists as a separate product at all. Clomiphene citrate is a mixture of two isomers: enclomiphene, which blocks oestrogen receptors at the hypothalamus and drives LH and FSH, and zuclomiphene, which is a weak oestrogen agonist with a half-life measured in weeks. Zuclomiphene accumulates for months on daily clomiphene, and it is the isomer generally blamed for the mood and visual complaints people report. Purifying the trans-isomer removes the long-lived half of the drug.
A ten-hour half-life on a daily schedule means modest accumulation — the interval is a little over two half-lives, so each dose lands on a small remainder. The level is therefore reasonably stable day to day and clears within a few days of stopping, which is a very different proposition from a compound whose active metabolite is still present a month later.
The downstream timescale is the one that matters for interpreting results, and it is much slower than the drug. Enclomiphene works by removing negative feedback, so the sequence is: LH and FSH rise within days, testicular testosterone production follows over weeks, and spermatogenesis — if that is the goal — responds over roughly three months, because that is how long the cycle takes. Bloodwork at six to eight weeks, which is what the app's entry specifies, is timed to that biology rather than to the pharmacokinetics. Enclomiphene is not FDA-approved; in the US it is supplied through compounding pharmacies.
One dose
pkCurve function — a
one-compartment absorption-and-elimination model with the absorption rate fitted so the
peak lands at the published time to peak.Dosed once daily
Charted at once daily because that is the daily oral schedule in the app's own dosing rows. It is what the numbers below are indexed to, not a recommendation about frequency — that is a prescribing decision.
The arithmetic behind those numbers
fraction left after one interval = 2^(−2.40) = 0.189
accumulation ratio = 1 ÷ (1 − 0.189) = 1.23
time to steady state ≈ 5 × half-life = 2.1 days
peak-to-trough = simulated, 1.245 ÷ 0.2802 = 4.44
The accumulation ratio is a closed form; the peak-to-trough figure is not. The generator adds up enough repeated curves for the total to stop changing, then reads the highest and lowest points of the last interval — which is what steady state means in practice. The vertical axis is relative, not a concentration: the shape and the ratios carry across people, the absolute levels do not.
The dosing rows this cadence came from
Established clinical use Reproduced from the app's entry so you can see what the chart above is indexed to. Which row applies to a particular person, if any, is a clinical decision this page does not make.
| Label | Amount | Route and frequency |
|---|---|---|
| Testosterone Restoration | 12.5-25mg/day | Daily oral |
| TRT Alternative | 25mg/day | Oral, morning |
When to draw bloodwork
The panel the app records for Enclomiphene is: Total T, Free T, LH, FSH, E2, Semen analysis (if fertility is goal), every 6-8 weeks when adjusting.. The pharmacokinetic point is the timing rather than the list: after any change, a level takes about 2.1 days to settle, so a panel drawn sooner measures something still moving. And because the peak-to-trough swing here is 4.44×, when in the interval you draw changes the result materially — a result without a stated draw time relative to the last dose is hard to compare with anything. Whether a result means anything is a question for the clinician who ordered it, read against the reference range your own lab printed. The lab-marker pages cover what the individual analytes measure.
Related: the interactive half-life calculator to try other cadences.
The app draws this curve from the doses you actually logged — your dates, your cadence — and projects seven days forward from the last one.
Save this dose to your log