Drug Interactions

Chelation

TRŞelasyon
Also known as:Chelate formation · Metal chelation

The formation of a stable ring-shaped complex between a metal ion and a molecule bearing two or more donor groups; in pharmacology it underlies both metal antidotes and important absorption interactions.

In depth

In drug interactions, tetracyclines, fluoroquinolones, bisphosphonates, dolutegravir and other integrase inhibitors, and penicillamine form poorly absorbed complexes with di- and trivalent cations (Ca²⁺, Mg²⁺, Al³⁺, Fe²⁺/Fe³⁺, Zn²⁺) in antacids, mineral supplements, dairy products and some fortified foods, sharply reducing their bioavailability.

Therapeutic chelating agents bind toxic or excess metals and promote their excretion: deferoxamine and deferasirox for iron, dimercaprol, succimer and sodium calcium edetate for lead and other heavy metals, and penicillamine for copper in Wilson disease.

Clinical pearl

Oral fluoroquinolones and tetracyclines should be separated from antacids, iron, calcium, zinc and dairy products by several hours, with the interval taken from the SmPC; taking the antibiotic first is usually advised.

Example drugs

Ciprofloxacin Doxycycline Alendronic acid Dolutegravir Deferoxamine Penicillamine
TRIn Turkish

Şelasyon

Bir metal iyonu ile iki veya daha fazla elektron verici grup taşıyan bir molekül arasında kararlı, halkalı bir kompleks oluşmasıdır; farmakolojide hem metal antidotlarının hem de önemli absorpsiyon etkileşimlerinin temelini oluşturur.

İlaç etkileşimlerinde tetrasiklinler, florokinolonlar, bisfosfonatlar, dolutegravir ve diğer integraz inhibitörleri ile penisilamin; antiasitlerde, mineral takviyelerinde, süt ürünlerinde ve bazı zenginleştirilmiş besinlerde bulunan iki ve üç değerlikli katyonlarla (Ca²⁺, Mg²⁺, Al³⁺, Fe²⁺/Fe³⁺, Zn²⁺) zor emilen kompleksler oluşturur ve biyoyararlanımları belirgin şekilde azalır.

Tedavi amaçlı şelatör ajanlar toksik veya fazla metalleri bağlayarak atılımlarını artırır: demir için deferoksamin ve deferasiroks; kurşun ve diğer ağır metaller için dimerkaprol, süksimer ve kalsiyum disodyum edetat; Wilson hastalığında bakır için penisilamin.

Oral florokinolonlar ve tetrasiklinler antiasitler, demir, kalsiyum, çinko ve süt ürünlerinden birkaç saat ayrı alınmalıdır (süre KÜB'e göre belirlenir); genellikle antibiyotiğin önce alınması önerilir.

Diğer adları:Şelat oluşumu · Metal şelasyonu
Updated 24.09.2026 1 views Educational reference — verify against current sources before clinical use.

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 Pharmacokinetic InteractionFarmakokinetik Etkileşim

An interaction in which one drug alters the absorption, distribution, metabolism or excretion of another, so that the concentrations of the affected drug change rather than its concentration–effect relationship.