Pharmacokinetics

Area Under the Curve AUC

TREğri Altındaki Alan
Also known as:Area under the concentration–time curve

The integral of the plasma drug concentration–time curve, measuring total systemic exposure to a drug over a specified interval or from zero to infinity; expressed in concentration × time units (e.g. mg·h/L).

Formula

AUC0–∞ = AUC0–t + Clast / λz AUC = F × Dose / CL

In depth

AUC is usually calculated from measured concentrations by the trapezoidal rule (AUC0–t) and extrapolated to infinity by adding Clast/λz, where Clast is the last quantifiable concentration and λz the terminal rate constant. With linear kinetics, AUC after a single dose is directly proportional to the dose reaching the circulation (F × Dose) and inversely proportional to clearance.

AUC is, with Cmax, a primary endpoint of bioequivalence studies and the main exposure measure in dose-proportionality and drug interaction studies. At steady state, the AUC over one dosing interval (AUCτ) equals the single-dose AUC0–∞ when kinetics are linear.

Clinical pearl

Some drugs are dosed to a target AUC rather than a peak or trough, for example carboplatin (Calvert formula), busulfan and vancomycin; a rise in AUC after adding an interacting drug signals reduced clearance or increased bioavailability.

Example drugs

Carboplatin Busulfan Vancomycin
TRIn Turkish

Eğri Altındaki Alan

Plazma ilaç konsantrasyonu–zaman eğrisinin integralidir; belirli bir aralıkta ya da sıfırdan sonsuza kadar ilaca toplam sistemik maruziyeti ölçer ve konsantrasyon × zaman birimiyle (örneğin mg·sa/L) ifade edilir.

AUC (EAA) genellikle ölçülen konsantrasyonlardan trapez kuralıyla hesaplanır (AUC0–t) ve Clast/λz eklenerek sonsuza ekstrapole edilir; burada Clast ölçülebilen son konsantrasyon, λz ise terminal hız sabitidir. Doğrusal kinetikte tek dozdan sonraki AUC, dolaşıma ulaşan dozla (F × Doz) doğru, klirensle ters orantılıdır.

AUC, Cmax ile birlikte biyoeşdeğerlik çalışmalarının birincil sonlanım noktalarından biri, doz orantılılığı ve ilaç etkileşimi çalışmalarında ise başlıca maruziyet ölçütüdür. Kinetik doğrusal olduğunda kararlı durumdaki bir doz aralığına ait AUC (AUCτ), tek dozun AUC0–∞ değerine eşittir.

Bazı ilaçlar doruk ya da çukur düzey yerine hedef AUC'ye göre dozlanır; karboplatin (Calvert formülü), busulfan ve vankomisin buna örnektir. Etkileşen bir ilaç eklendikten sonra AUC'nin artması klirensin azaldığını veya biyoyararlanımın arttığını gösterir.

Diğer adları:EAA · Konsantrasyon–zaman eğrisi altındaki alan
Updated 24.09.2026 0 views Educational reference — verify against current sources before clinical use.

Read next

BioavailabilityBiyoyararlanım

The fraction of an administered dose that reaches the systemic circulation unchanged, and the rate at which it does so; by definition, bioavailability is 1 (100%) for an intravenous dose.

 ClearanceKlirens

The rate at which a drug is removed from the body, primarily by the liver and kidneys, representing the volume of plasma cleared of the drug per unit time.

 Maximum Plasma ConcentrationMaksimum Plazma Konsantrasyonu

The highest (peak) drug concentration observed in plasma after administration of a dose, read directly from the measured concentration–time profile.

 BioequivalenceBiyoeşdeğerlik

The absence of a significant difference in the rate and extent of absorption of the active substance when two pharmaceutically equivalent or alternative products are given at the same molar dose under similar conditions.

 Linear PharmacokineticsDoğrusal Farmakokinetik

Pharmacokinetic behaviour in which parameters such as clearance, volume of distribution and half-life do not change with dose or time, so that plasma concentrations and AUC increase in direct proportion to dose.

 Therapeutic Drug MonitoringTerapötik İlaç İzlemi

The measurement of drug concentrations in blood at defined times, interpreted in the clinical context, to individualise dosing so as to maximise efficacy and minimise toxicity.