1. What is the Cockcroft-Gault Formula?

The Cockcroft-Gault formula estimates creatinine clearance (CrCl) from serum creatinine, age, weight, and gender. It is widely used for drug dosing adjustments in patients with renal impairment and provides an estimate of renal function.

2. How Does the Calculator Work?

The calculator uses the Cockcroft-Gault equation:

Where:

• \( Age \) — Age in years
• \( Weight \) — Body weight in kilograms
• \( SCr \) — Serum creatinine in mg/dL
• \( 0.85 \) — Female gender adjustment factor

Explanation: The formula estimates creatinine clearance based on demographic and laboratory parameters, with adjustment for gender differences in muscle mass.

3. Importance of CrCl Calculation

Details: Creatinine clearance estimation is essential for drug dosing adjustments, assessing renal function, and guiding treatment decisions in patients with kidney disease.

4. Using the Calculator

Tips: Enter age in years, weight in kilograms, serum creatinine in mg/dL, and select gender. All values must be valid (age 1-120 years, weight > 0 kg, SCr > 0 mg/dL).

5. Frequently Asked Questions (FAQ)

Q1: Why use Cockcroft-Gault formula?
A: It is one of the most widely validated equations for estimating creatinine clearance and is commonly used for drug dosing adjustments.

Q2: What are normal CrCl values?
A: Normal CrCl is approximately 90-120 mL/min for young adults, declining with age. Values below 60 mL/min indicate renal impairment.

Q3: When should creatinine clearance be measured?
A: When assessing renal function for drug dosing, evaluating kidney disease progression, or monitoring patients with known renal impairment.

Q4: Are there limitations to this formula?
A: Less accurate in extremes of age, obesity, malnutrition, amputees, and patients with rapidly changing renal function.

Q5: Should ideal body weight be used?
A: For obese patients, some guidelines recommend using ideal body weight rather than actual body weight for more accurate estimation.