Dose, Response & Safety

Dose–Response Curves: Graded, Quantal, and How to Read Them

One picture underlies almost every dosing decision in medicine: the dose–response curve. But there are really two curves wearing the same name — one drawn from a single patient whose response grows smoothly with dose, and one drawn from a whole population where each person simply responds or doesn't. Learn to tell them apart, learn to read potency from efficacy at a glance, and the rest of pharmacodynamics falls into place.

Therapeutic Index and the Margin of Safety: Which Drugs Need Monitoring

Two drugs can both "work." One you prescribe and forget; the other you check with a blood test every few weeks, because the dose that helps and the dose that harms sit almost on top of each other. That gap — wide or terrifyingly narrow — is the therapeutic index. This chapter turns the quantal curves you just met into the single most practical safety number in medicine, and shows you exactly which drugs earn a needle in the arm.