carboplatin dose calculator

What this carboplatin dose calculator does

This page helps you estimate a carboplatin dose from a target drug exposure (AUC) and kidney function. Carboplatin is commonly dosed with the Calvert formula rather than by body surface area alone. The key idea is simple: better kidney function clears carboplatin faster, so the dose needed to reach a specific AUC is usually higher.

The calculator above uses a practical workflow many clinicians know: estimate creatinine clearance (CrCl) with Cockcroft-Gault, treat that as a GFR estimate, optionally apply a GFR cap (often 125 mL/min), then calculate dose in mg. It also includes weight-method selection (actual, ideal, adjusted, or auto) and optional dose rounding.

Core formula used

Calvert formula

Dose (mg) = Target AUC × (GFR + 25)

• Target AUC is chosen by the treatment protocol.
• GFR is typically estimated from labs and demographics in routine practice.
• +25 represents non-renal clearance in the original model.

Kidney function estimate in this tool

By default, the calculator estimates kidney function with the Cockcroft-Gault equation:

CrCl (mL/min) = ((140 − age) × weight in kg) / (72 × SCr in mg/dL)
Multiply by 0.85 for females.

Because weight choice matters, this tool lets you use actual body weight, ideal body weight (IBW), or adjusted body weight (AdjBW). In Auto mode, it switches to AdjBW if actual body weight is more than 120% of IBW.

How to use the calculator

1. Enter the protocol target AUC.
2. Enter age, sex, body weight, and height.
3. Enter serum creatinine and unit (mg/dL or µmol/L).
4. Pick a weight method for Cockcroft-Gault.
5. Decide whether to apply a GFR cap and dose rounding.
6. Click Calculate Dose.

The result area shows the final carboplatin dose, the intermediate CrCl estimate, and the assumptions used. That transparency is useful when double-checking a plan or documenting a calculation.

Why dose assumptions matter

1) Serum creatinine handling

Very low SCr can overestimate kidney function. Many workflows set a minimum SCr floor (commonly 0.7 mg/dL) to avoid unrealistically high CrCl values in frail or low-muscle-mass patients. This option is enabled by default.

2) GFR capping

Some regimens cap calculated GFR (often at 125 mL/min) to limit excessive doses in very high estimated filtration. Whether and where to cap depends on local policy and protocol language.

3) Weight method choice

Weight selection can significantly change CrCl. In larger body size ranges, adjusted body weight is often used when actual body weight substantially exceeds IBW. Always align with your institutional standard.

4) Dose rounding

Pharmacies may round to practical vial increments (for example nearest 5 mg or 10 mg). The calculator can display unrounded or rounded output so the prescriber and pharmacy can agree on the final prepared dose.

Common target AUC values (context only)

AUC targets vary by disease, line of therapy, and combination partner. You may see values such as 4, 5, 6, or 7 in different protocols. The correct AUC is not chosen by this tool—it must come from a validated treatment plan.

Example walkthrough

Suppose a patient has target AUC 5, estimated GFR/CrCl 70 mL/min after all protocol adjustments, and no additional modifications.

• Dose = 5 × (70 + 25)
• Dose = 5 × 95
• Dose = 475 mg

If your site rounds to nearest 5 mg, the value remains 475 mg. If nearest 10 mg is required, it may round to 480 mg.

Frequently asked questions

Is this calculator valid for every patient?

No. Special populations (for example dialysis, rapidly changing renal function, unusual body composition, or protocol-specific adjustments) require individualized assessment.

Should I use measured GFR when available?

Many teams prefer measured GFR in selected scenarios because it may improve precision. If measured GFR is available and your protocol supports it, follow that pathway.

Does this replace pharmacist or oncologist review?

Absolutely not. It is a supporting calculator only. Final prescribing and verification belong to licensed clinical professionals.