OATP1B1, encoded by SLCO1B1, is the main transporter that pulls statins out of the blood and into hepatocytes for metabolism and biliary excretion. The common reduced-function allele (rs4149056, c.521T>C) slows this uptake, so the drug lingers in plasma — clinically this is the strongest known genetic predictor of simvastatin-induced myopathy (SEARCH trial, CPIC guideline).
dC/dt = -k_elim · C
k_elim = k_base · [1 - (1-g)·d] + k_renal
AUC(t) = ∫ C dt
Risk = 100 · (1 - e^(-AUC/τ))
Here g is the genotype's relative transporter function (TT=1.0, TC≈0.65, CC≈0.35), d is how OATP1B1-dependent the chosen statin's clearance is (simvastatin high, rosuvastatin lower — it leans more on other pathways), and k_renal is a small genotype-independent clearance floor. This 2D build renders the same equations two ways at once: a scrolling strip chart plots C(t) directly (with the shaded band showing how fast the AUC integral is filling), while a schematic flow diagram sends dose "packets" from the gut into a plasma pool, where each pass through the liver gate has capture probability proportional to k_elim — mathematically the discrete Monte-Carlo capture rate converges to the same continuous first-order decay used for the concentration curve.
- Genotype buttons — set the transporter function factor g.
- Statin buttons — set how OATP1B1-dependent clearance is (d) and the risk time-constant τ.
- Dose slider + Administer Dose — adds a bolus to plasma concentration; click repeatedly to simulate repeated daily dosing and watch accumulation on the strip chart.
- Flow diagram — dose packets travel Gut → Plasma → Liver gate; capture removes them (cleared), a miss routes them out to Muscle and back to Plasma (still circulating, still exposing tissue), matching the risk gauge's glow.