1. What is the Cockcroft-Gault Formula?

The Cockcroft-Gault formula estimates creatinine clearance (CrCl) from serum creatinine, age, weight, and gender. It's commonly used for drug dosing adjustments in patients with renal impairment.

2. How Does the Calculator Work?

The calculator uses the Cockcroft-Gault formula:

For females, the result is multiplied by 0.85

Where:

• \( Age \) — Age in years
• \( Weight \) — Weight in kilograms
• \( Cr \) — Serum creatinine (mg/dL)

Explanation: The formula estimates the rate at which creatinine is cleared from the blood by the kidneys.

3. Importance of CrCl Calculation

Details: CrCl estimation is crucial for adjusting medication dosages in patients with kidney impairment to avoid toxicity or underdosing.

4. Using the Calculator

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

5. Frequently Asked Questions (FAQ)

Q1: Why use Cockcroft-Gault formula?
A: It's simple and widely used for drug dosing adjustments, though newer equations may be more accurate for GFR estimation.

Q2: What are normal CrCl values?
A: Normal is approximately 95-125 mL/min for young men and 85-115 mL/min for young women, declining with age.

Q3: When should creatinine be measured?
A: Morning fasting sample is ideal, but random samples are acceptable. Avoid testing after meat-heavy meals or vigorous exercise.

Q4: Are there limitations to this formula?
A: Less accurate in extremes of age/weight, obese patients, amputees, and those with rapidly changing kidney function.

Q5: Should ideal body weight be used?
A: For obese patients, some protocols recommend using adjusted body weight or ideal body weight in the calculation.