Carboplatin Calculator

This carboplatin calculator (carboplatin dose calculator) estimates your total carboplatin dose (in mg) using the Calvert formula). The evaluations are based on a person's creatinine clearance calculations (found using the Cockcroft - Gault equation), and the targeted carboplatin AUC value.

We try our best to make our Omni Calculators as precise and reliable as possible. However, this tool can never replace professional medical advice.

Carboplatin is a chemotherapy medication used to treat some forms of cancer (e.g., lung, ovarian, or brain cancer). It is administered via injection into a vein. After 24 hours, 70% of this drug is excreted unchanged in the urine. Therefore, the dose depends on the function of the kidneys. We use the following Calvert formula to calculate kidney function:

Carboplatin dose (mg) = AUC × (GFR + 25)

where:

• AUC - the Area Under the Curve for carboplatin; and

• GRF - Glomerular Filtration Rate (see: GFR calculator.).

The maximum recommended carboplatin dose is calculated with a GFR estimate capped to 125 ml/min for patients with normal renal function. To compute the maximum dose your patient can receive, use the equation:

Maximum carboplatin dose (mg) = AUC × (125 ml/min + 25)

Maximum carboplatin dose (mg) = AUC × 150

As you can see, the maximum dose depends mostly on the target AUC.

Area under the curve (AUC) is a term that frequently used in pharmacokinetics. It describes the variation of a drug's concentration in the blood's plasma as a function of time. In practice, the trapezoidal rule is used to estimate AUC, and the drug's concentration is measured at certain discrete points in time.

Target carboplatin AUC values of 5 and 7 mg/ml/min are recommended.

This carboplatin AUC calculator uses the above method to find your carboplatin dose.

Our carboplatin calculator computes the carboplatin dose in two steps:

1. Calculating GFR using the Cockcroft-Gault equation:

MEN: GFR = ((140 - A) × W / (72 × Cr)

WOMEN: GFR = 0.85 × GFR formula for men

where:

`GRF`- Glomerular Filtration Rate

`A` - age (years)

`W` - weight (kg)

`Cr` - serum creatinine (mg/dL)

Let's have a look at the example below:

We want to find the GFR of a 50 year old man who weighs 78 kilograms, and has a serum creatinine level of 1.2 mg/dL.

GFR = ((140 - 50) × 78 / (72 × 1.2)

GFR = (90 × 78) / (72 × 1.2)

GFR = (90 × 78) / (72 × 1.2)

GFR = 7020 / 86.4

GFR = 7020 / 86.4

GFR = 81.25 ml/min

2. 2. Once we have found GFR, we can use the Calvert formula (described above) to calculate the optimal carboplatin dose for the patient.

Example (continued):

Knowing the GFR of a patient and using the target AUC value of 6 mg/ml/min, we can calculate carboplatin dose for the patient.

Carboplatin dose (mg) = AUC × (GFR + 25)

Carboplatin dose (mg) = 7 × (81.25 + 25)

Carboplatin dose (mg) = 7 × 106.25

Carboplatin dose (mg) = 743.8

Our carbo calculator allows you to make all of the above calculations in seconds!

Additional considerations:

• If your patient is overweight or obese (calculated BMI ≥ 25 kg/m²), consider using adjusting body weight for your carboplatin dose calculator.

  adjusted BW [kg] = (IBW) + 0.4 × (CBW – IBW)

  where IBW stands for ideal body weight, and CBW stands for current weight.

• If your patient has low serum creatinine levels, consider using a minimum creatinine level of 0.7 mg/dL to avoid an overestimation of GFR.

• Consider using EDTA or 24-hour urine to measure creatinine clearance (not a mathematical equation) when dosing at an AUC > 6, or when using an un-capped creatinine clearance.

• Calvert AH. et al. Carboplatin dosage: prospective evaluation of a simple formula based on renal function. J Clin Oncol. 1989

• Hemoglobin E and glucose-6-phosphate Deficiency in the Khmer Air Force (Cambodia)

• NCCN Chemotherapy Order Templates

• Cockcroft DW. Prediction of creatinine clearance from serum creatinine. Nephron. 1976