1. What is the Cockcroft-Gault Formula?

The Cockcroft-Gault formula estimates creatinine clearance (CrCl) which correlates with glomerular filtration rate (GFR). 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:

Where:

• \( age \) — Age in years
• \( weight \) — Body weight in kg
• \( SCr \) — Serum creatinine (mg/dL)
• 0.85 — Correction factor for female gender

Explanation: The formula accounts for age-related decline in kidney function, body size, and gender differences in muscle mass.

3. Importance of CrCl Calculation

Details: CrCl estimation is crucial for adjusting medication dosages in patients with renal impairment, particularly for drugs with narrow therapeutic windows.

4. Using the Calculator

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

5. Frequently Asked Questions (FAQ)

Q1: Why use Cockcroft-Gault instead of other equations?
A: It's widely validated for drug dosing adjustments and remains the standard for many medication guidelines.

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

Q3: Should actual or ideal body weight be used?
A: For obese patients, some recommend using ideal body weight or adjusted body weight.

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

Q5: How often should CrCl be recalculated?
A: Should be reassessed with significant changes in weight, creatinine, or clinical status.