Clinical Pharmacology & Dosing

Creatinine Clearance CrCl

TRKreatinin Klirensi
Also known as:CLCr · Creatinine clearance rate

The volume of plasma cleared of creatinine per unit time, used as a clinical index of glomerular filtration rate and as the basis of most renal dosing recommendations.

Formula

CrCl = (UCr × V) / (SCr × t)

In depth

CrCl can be measured from a timed (usually 24-hour) urine collection with a simultaneous serum creatinine (UCr = urine creatinine concentration, V = urine volume, t = collection time, SCr = serum creatinine), or estimated with the Cockcroft–Gault equation; it is expressed in mL/min and is not normalised to body surface area. Because creatinine is filtered and also secreted by the tubules, CrCl overestimates true GFR, increasingly so as kidney function declines.

Serum creatinine depends on muscle mass and diet, so CrCl is unreliable in cachexia, amputation, extremes of body weight and acute kidney injury. Drugs that inhibit tubular creatinine secretion, such as trimethoprim, cimetidine, dolutegravir and cobicistat, raise serum creatinine without reducing GFR.

Clinical pearl

A small rise in serum creatinine after starting trimethoprim, dolutegravir or cobicistat usually reflects inhibited tubular secretion rather than kidney injury; progressive rises warrant investigation.

Example drugs

Trimethoprim Cimetidine Dolutegravir Cobicistat
TRIn Turkish

Kreatinin Klirensi

Birim zamanda kreatininden temizlenen plazma hacmidir; glomerüler filtrasyon hızının klinik bir göstergesi ve böbrek fonksiyonuna göre doz önerilerinin çoğunun temeli olarak kullanılır.

Kreatinin klirensi, eş zamanlı serum kreatinini ile birlikte zamanlı (genellikle 24 saatlik) idrar toplanarak ölçülebilir (UCr = idrar kreatinin konsantrasyonu, V = idrar hacmi, t = toplama süresi, SCr = serum kreatinini) ya da Cockcroft–Gault formülüyle tahmin edilebilir; vücut yüzey alanına göre normalize edilmeden mL/dk olarak ifade edilir. Kreatinin glomerüllerden süzülmenin yanı sıra tübüllerden de salgılandığından kreatinin klirensi gerçek GFR'yi olduğundan yüksek gösterir ve bu fark böbrek fonksiyonu azaldıkça artar.

Serum kreatinini kas kütlesine ve diyete bağlı olduğundan kaşeksi, amputasyon, uç vücut ağırlıkları ve akut böbrek hasarında kreatinin klirensi güvenilir değildir. Trimetoprim, simetidin, dolutegravir ve kobisistat gibi tübüler kreatinin sekresyonunu inhibe eden ilaçlar GFR'yi azaltmadan serum kreatininini yükseltir.

Trimetoprim, dolutegravir veya kobisistat başlandıktan sonra serum kreatininindeki hafif artış genellikle böbrek hasarını değil tübüler sekresyonun inhibisyonunu yansıtır; ilerleyici artışlar ise araştırılmalıdır.

Diğer adları:Kreatinin klerensi
Updated 24.09.2026 0 views Educational reference — verify against current sources before clinical use.

Read next

Cockcroft–Gault EquationCockcroft–Gault Formülü

An equation that estimates creatinine clearance in adults from age, body weight, sex and serum creatinine, and is widely used to guide renal dose adjustment.

 Estimated Glomerular Filtration RateTahmini Glomerüler Filtrasyon Hızı

An estimate of glomerular filtration rate calculated from serum creatinine and/or cystatin C together with age and sex, conventionally expressed per 1.73 m² of body surface area.

 Renal ClearanceRenal Klirens

The component of total clearance attributable to the kidneys: the volume of plasma cleared of drug by urinary excretion per unit time.

 Renal Dose AdjustmentBöbrek Fonksiyonuna Göre Doz Ayarlaması

The modification of the dose or dosing interval of a drug that is cleared, or has active or toxic metabolites cleared, by the kidneys, to prevent accumulation and toxicity in renal impairment.

 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.

 NephrotoxicityNefrotoksisite

Drug- or chemical-induced damage to kidney structure or function, presenting as acute kidney injury, tubular dysfunction, electrolyte disturbances or progressive chronic kidney disease.