Drug Metabolism & Transporters

Autoinduction

TROtoindüksiyon
Also known as:Auto-induction · Self-induction

Induction by a drug of the enzymes responsible for its own metabolism, so that its clearance increases and its concentrations fall over time during continued dosing at the same dose.

In depth

Autoinduction produces time-dependent (non-stationary) pharmacokinetics: parameters estimated after the first dose overpredict exposure at steady state. Carbamazepine is the classic example; it induces CYP3A4, its main metabolic pathway, and its half-life shortens substantially over the first weeks of therapy. Other examples include rifampicin, phenobarbital, efavirenz (CYP2B6) and artemisinin.

The process takes one to several weeks to complete, depending on enzyme turnover, so drug levels measured early in therapy may not reflect the eventual steady state.

Clinical pearl

Carbamazepine is started low and titrated upward partly because of autoinduction; a level that is adequate in the first week may become subtherapeutic a few weeks later on the same dose.

Example drugs

Carbamazepine Rifampicin Efavirenz Artemisinin
TRIn Turkish

Otoindüksiyon

Bir ilacın kendi metabolizmasından sorumlu enzimleri indüklemesi; böylece aynı dozla sürdürülen tedavide zamanla klirensinin artması ve konsantrasyonlarının düşmesidir.

Otoindüksiyon zamana bağımlı (durağan olmayan) farmakokinetiğe yol açar: ilk dozdan sonra hesaplanan parametreler kararlı durumdaki maruziyeti olduğundan yüksek tahmin eder. Klasik örnek karbamazepindir; ilaç başlıca metabolik yolu olan CYP3A4'ü indükler ve yarılanma ömrü tedavinin ilk haftalarında belirgin şekilde kısalır. Diğer örnekler rifampisin, fenobarbital, efavirenz (CYP2B6) ve artemisinindir.

Süreç, enzim yenilenme hızına bağlı olarak bir ile birkaç hafta içinde tamamlanır; bu nedenle tedavinin erken döneminde ölçülen ilaç düzeyleri nihai kararlı durumu yansıtmayabilir.

Karbamazepine düşük dozla başlanıp dozun kademeli olarak artırılmasının nedenlerinden biri otoindüksiyondur; ilk hafta yeterli olan bir düzey, aynı dozda birkaç hafta sonra subterapötik hâle gelebilir.

Diğer adları:Oto-indüksiyon · Kendi metabolizmasını indükleme
Updated 24.09.2026 0 views Educational reference — verify against current sources before clinical use.

Read next

Enzyme InductionEnzim İndüksiyonu

An increase in the amount and activity of a drug-metabolizing enzyme or transporter, usually through enhanced gene transcription, caused by repeated exposure to a drug or other xenobiotic.

 Steady-State ConcentrationKararlı Durum Konsantrasyonu

The constant plasma drug concentration achieved when the rate of drug administration equals the rate of elimination during repeated dosing.

 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.

 Dose TitrationDoz Titrasyonu

The stepwise adjustment of a drug's dose, usually upwards, according to therapeutic response and tolerability until the target effect or target dose is reached.

 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.

 ToleranceTolerans

A gradual reduction in response to a drug with repeated or continuous exposure, so that a higher dose is needed to reproduce the original effect; it develops over days to weeks.