Three small interactive tools that illustrate ideas from our articles. Everything runs in your browser. Educational only, not medical or dosing advice.
See how potency (EC50) and efficacy (Emax) change the shape of a concentration-response curve. The grey curve is a reference full agonist. This is a teaching model only; it says nothing about the dose of any real medicine.
Simple occupancy theory says the fraction of receptors bound at equilibrium is C / (C + Kd), where C is the free drug concentration and Kd is the dissociation constant (a measure of affinity). Enter both in the same units to see the result. Real tissues are more complicated, so treat this as a classroom illustration.
Six short questions on the ideas explained in our articles. Your answers stay in your browser.