Dose-Response Curve Lab — Therapeutic Window (2D)

Dose & Curve Shape

Dose (log scale) 1.0

Potency EC50 5.0

Efficacy Emax 100%

Hill coefficient n 2.0

Toxic threshold TC50 50

Hormetic strength 0.20

Live Readout

Effect

Toxicity risk

Net benefit

Therapeutic index

1.0

Therapeutic window

0.1 – 1.0

How it works

This 2D companion trades the 3D version's orbiting cell field for the tool pharmacologists actually read: a live dose-response curve on a logarithmic dose axis, exactly as it appears in a drug-label graph or a toxicology report.

Effect:   E(D) = Emax * D^n / (EC50^n + D^n)
Hormesis: E(D) = Emax * (1 + h*(D/EC50)) / (1 + (D/EC50)^n)
Risk:     R(D) = 100 / (1 + (TC50/D)^3)
Therapeutic index = TC50 / EC50

Dose — drag the slider or drag directly on the chart to move the vertical dose marker; auto-sweep pauses the moment you touch either control.
Potency (EC50) and Hill coefficient n — set where the effect curve sits on the log-dose axis and how steeply it rises (receptor cooperativity).
Toxic threshold (TC50) — the dose at which the separate toxicity curve crosses half-maximal risk; the shaded band between the effect curve's 20%-of-max crossing and this threshold is the therapeutic window.
Hormesis toggle — swaps the standard monotonic Hill curve for a Brain-Cousens biphasic curve, where a small dose stimulates (the effect rises above baseline before EC50) and only larger doses inhibit — the pattern real hormetic agents (low-dose radiation, alcohol, many toxins) show experimentally.

A wide therapeutic index (TC50 far above EC50) is what makes a drug forgiving of dosing error; a narrow one — like digoxin or lithium — is why those drugs need blood-level monitoring in real clinical practice.

Effect curve Toxicity curve Therapeutic window

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