Codeine Prodrug Activation: CYP2D6 Genotype Simulator (2D)

Codeine is a prodrug: it must be bio-activated by the liver enzyme CYP2D6 into morphine before it can relieve pain, and how much morphine forms depends entirely on a patient's CYP2D6 genotype. This 2D companion simulator drives the same real two-compartment pharmacokinetic model as its 3D counterpart — a gut depot, a plasma codeine compartment fed by absorption and drained by CYP2D6 conversion plus other clearance routes, and a plasma morphine compartment fed by that conversion and drained by elimination — and renders it as live compartment bars plus a real-time concentration-vs-time chart. Switching between Poor, Intermediate, Normal and Ultra-rapid Metabolizer shows the same oral dose swing from therapeutic failure, to normal analgesia, to a documented toxicity risk — the exact mechanism behind codeine's contraindication in children and breastfeeding mothers with the ultra-rapid phenotype.