# Carboplatin Dose Calculator (Calvert Formula)

Calculate carboplatin dose using the Calvert formula (AUC x [GFR + 25]). Includes FDA-recommended GFR cap at 125 mL/min to prevent overdosing.

## What this calculates

Carboplatin dosing is based on the Calvert formula, which uses target AUC and kidney function instead of body surface area. Enter the target AUC from the treatment protocol and the patient's GFR to calculate the carboplatin dose in milligrams.

## Inputs

- **Target AUC** (mg/mL x min) — min 1, max 10 — Typical values: 2-7 depending on regimen
- **GFR (or CrCl)** (mL/min) — min 5, max 200 — Glomerular filtration rate or creatinine clearance

## Outputs

- **Carboplatin Dose** — Calculated dose using Calvert formula
- **Dose (GFR capped at 125)** — Dose with GFR capped at 125 mL/min per FDA guidance
- **Formula Used** — formatted as text — The Calvert formula with your values
- **GFR Cap Note** — formatted as text — Whether the GFR cap was applied

## Details

The Calvert formula is the standard method for dosing carboplatin:

**Dose (mg) = Target AUC x (GFR + 25)**

Unlike most chemotherapy agents dosed by body surface area, carboplatin is dosed by kidney function because it is primarily cleared renally. The AUC (area under the concentration-time curve) represents the total drug exposure, and the formula adjusts for each patient's ability to clear the drug.

**Typical target AUC values by regimen:**

- **AUC 2:** Weekly low-dose regimens
- **AUC 4-5:** Combination therapy (e.g., with paclitaxel for ovarian cancer)
- **AUC 5-6:** Single-agent therapy
- **AUC 6-7:** Dose-intensive regimens (e.g., testicular cancer)

**FDA GFR cap at 125 mL/min:** In 2010, the FDA recommended capping the GFR at 125 mL/min when calculating carboplatin doses. This was in response to reports of toxicity in patients whose GFR was overestimated by the Cockcroft-Gault or Jelliffe equations when used with newer, standardized (IDMS) creatinine assays. This calculator shows both the uncapped and capped dose.

**GFR measurement:** The Calvert formula was originally validated using Cr-51 EDTA clearance (a measured GFR, not estimated). In practice, most institutions use creatinine clearance estimated by the Cockcroft-Gault equation. Using eGFR from the CKD-EPI equation is generally not recommended for carboplatin dosing without institutional guidance.

This calculator is for educational purposes. Chemotherapy dosing requires verification by a pharmacist and oncologist.

## Frequently Asked Questions

**Q: Why is carboplatin dosed by GFR instead of body surface area?**

A: Carboplatin is primarily eliminated by the kidneys through glomerular filtration. The Calvert formula directly accounts for renal clearance, which makes dosing more precise than BSA-based methods. BSA-based dosing would give the same dose to two patients of similar size even if one had significantly worse kidney function, leading to higher toxicity in the patient with reduced clearance.

**Q: Should I use GFR or creatinine clearance?**

A: The Calvert formula was validated using measured GFR (Cr-51 EDTA clearance). In clinical practice, most institutions use estimated creatinine clearance from the Cockcroft-Gault equation. The CKD-EPI eGFR equation is generally not recommended for carboplatin dosing because it was not validated for this purpose. Check your institution's pharmacy guidelines.

**Q: What happens if the dose is too high?**

A: Carboplatin overdosing primarily causes myelosuppression, especially thrombocytopenia (low platelets). Other toxicities include nausea, nephrotoxicity, and ototoxicity. The FDA's GFR cap at 125 mL/min was introduced specifically to prevent overdosing in patients whose creatinine clearance is overestimated by newer lab assays.

**Q: Can this calculator be used for pediatric patients?**

A: The Calvert formula is used in both adult and pediatric oncology, but pediatric dosing may use different GFR estimation methods (such as the Schwartz equation). Always follow your institution's pediatric oncology protocols. This calculator does not include pediatric-specific adjustments.

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Source: https://vastcalc.com/calculators/health/carboplatin
Category: Health & Fitness
Last updated: 2026-04-08