How to read a blood-level curve
May 2026 · 5 min read
Every projected blood-level chart in Autus is telling you the same three things. Learn to read them and most dosing questions answer themselves.
Peak (Cmax)
The top of the curve. For a fast compound, the peak is sharp and early; for a long ester, it’s a gentle hill days after injection. A high peak isn’t automatically good — for some compounds it’s where side effects live.
Trough
The low point right before your next dose. Troughs are where long-ester TRT lives or dies: if your level swings from a high peak to a low trough, you feel it. Tightening the trough — smaller, more frequent doses — is usually what “smoothing out” a protocol means.
Time-in-range
How long you spend inside the band you’re aiming for. This is the number titration is really optimizing. Two protocols can share a peak and a trough but spend very different amounts of time where you want to be.
Putting it together
When you compare 0.5 mg split twice daily against 1 mg once daily, you’re comparing two curves with the same area under them but very different shapes. The split version trades a lower peak for a higher trough and more time-in-range. Whether that’s the right trade depends on the compound and your goal — the chart just makes the trade visible.