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Reading the PK/PD sections ​

When you select a compound in the timeline, the inspector shows several PK/PD-specific sections under the standard header. They're laid out top-to-bottom in roughly chronological order (what happens first → what happens last). This page walks each one.

Earlier versions of Lab opened a separate "PK/PD drawer" overlay. The drawer is gone — these sections now live inline in the inspector itself, so you can read PK/PD detail without losing your timeline context. Enzyme detail still gets its own dedicated view (see below).

Biological Effects ​

Every PD effect the compound exerts, with the receptor or target it binds and the response it produces. Each row carries citation pills — green for literature-anchored magnitudes, blue for calibrations.

Click any row to expand: affinity (Ki / Kd), response time constant (τ), and the full source list for that effect.

Active interactions ​

If the compound is participating in any interactions on the current timeline, they appear here in severity order. A "Find more synergy" link surfaces beneficial pairings you haven't added yet.

Subject impact ​

How your physiology shifts the drug's behavior — sex, age, conditions, and bloodwork-derived multipliers on absorption, distribution, and clearance.

Clearance ​

Hepatic, renal, and biliary breakdown of where the drug goes. Each enzyme involved is a clickable chip that opens the enzyme detail panel for that enzyme.

Effects on other drugs ​

What enzymes this compound inhibits or induces, and the magnitude. Useful for predicting why your other compounds might be behaving unexpectedly.

Absorption + binding ​

  • Bioavailability — % of dose that reaches systemic circulation
  • Protein binding % — free vs. bound drug. Free fraction is what causes effects.
  • Half-life — time for concentration to halve
  • Tmax / Cmax — time-to-peak and peak concentration

References ​

Collapsed by default. Numbered entries match every pill across every section above. Click any pill above to auto-expand and scroll to the matching entry.

The enzyme detail panel ​

When you click an enzyme chip in the Clearance section (or anywhere else an enzyme is named), a dedicated enzyme detail panel replaces the inspector view. It shows:

  • The enzyme's current activity multiplier (1.00 = your baseline) at the playhead
  • A sparkline showing how it's evolved across the simulation
  • "How it's composed" — every factor pushing the activity above or below 1.00
  • "Active modulators" — every timeline item currently inhibiting or inducing this enzyme, with click-through to those items

Use the back arrow to return to the inspector view.

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