Chemotherapy Dose Calculator (USA)
Calculate chemotherapy dosing based on Body Surface Area (BSA). For educational purposes only.
How Chemotherapy Dosing is Calculated
Chemotherapy dosing is calculated using Body Surface Area (BSA) and drug-specific constants:
This calculation ensures safe and effective chemotherapy administration based on patient size.
- BSA: Body Surface Area in square meters
- Drug Constant: Standardized dose per square meter
- Common Agents: Cisplatin, Carboplatin, Paclitaxel, Doxorubicin
- BSA Formula: Mosteller: √(Height(cm) × Weight(kg) / 3600)
Chemotherapy Dose Calculator
Dose Visualization
Dose Amount
Dose Calculation Breakdown
BSA Calculation:
√(170 × 70 / 3600) = 1.8 m²
Dose Formula:
1.8 m² × 75 mg/m² = 135 mg
Cycle Information:
Every 3 weeks
Dose Per Cycle:
135 mg
This calculator provides estimates only. Always verify with a pharmacist or oncologist before administration.
- Confirm patient allergies
- Verify kidney function if needed
- Check for drug interactions
- Follow institutional protocols
- Document all doses given
Understanding Chemotherapy Dosing
Body Surface Area (BSA)-based dosing calculates chemotherapy doses according to the patient's body size. This approach provides a more accurate dosing metric than weight alone, as BSA correlates better with organ function and drug metabolism.
Mosteller Formula
Most commonly used formula in clinical practice.
Alternative Formulas
- DuBois: 0.007184 × Height^0.725 × Weight^0.425
- Haycock: 0.024265 × Height^0.3964 × Weight^0.5378
- Gehan & George: 0.0235 × Height^0.42246 × Weight^0.51456
- Performance status
- Age (elderly may need dose reduction)
- Kidney function
- Liver function
- Previous treatment toxicity
- Concurrent medications
- Pregnancy status
Common Chemotherapy Agents
| Agent | Standard Dose | Indications | Major Toxicities | Dose Limits |
|---|---|---|---|---|
| Cisplatin | 75 mg/m² | Testicular, ovarian, bladder cancer | Nephrotoxicity, neurotoxicity | Monitor kidney function |
| Carboplatin | 50 mg/m² | Ovarian, lung cancer | Myelosuppression | Adjust for AUC |
| Paclitaxel | 175 mg/m² | Breast, ovarian, lung cancer | Neutropenia, neuropathy | Pre-medicate for hypersensitivity |
| Doxorubicin | 60 mg/m² | Breast, lymphoma, sarcoma | Cardiotoxicity | Lifetime max 550 mg/m² |
| Cyclophosphamide | 100 mg/m² | Lymphoma, breast cancer | Hemorrhagic cystitis | Monitor for bladder toxicity |
| Gemcitabine | 25 mg/m² | Pancreatic, lung, breast cancer | Myelosuppression | Weekly dosing common |
Chemotherapy Dosing Quiz
Select the correct formula:
The correct answer is a) BSA (m²) × Drug Constant (mg/m²). The formula multiplies the patient's Body Surface Area by the standardized drug constant.
Memorize the fundamental formula for BSA-based chemotherapy dosing.
Select the correct formula:
The correct answer is a) √(Height × Weight / 3600). The Mosteller formula calculates BSA as the square root of (Height in cm × Weight in kg) divided by 3600.
Memorize the Mosteller formula for BSA calculation.
Select the agent with cardiotoxicity concerns:
The correct answer is b) Doxorubicin. Doxorubicin has a lifetime cumulative dose limit of 550 mg/m² due to risk of irreversible cardiotoxicity.
Identify chemotherapy agents with cumulative toxicity limits.
Q&A
Q: When should we adjust chemotherapy doses based on BSA?
A: BSA-based dosing is standard for most chemotherapy agents, but adjustments may be needed:
When to Reduce Dose:
- Age >70 years (consider 10-15% reduction)
- Poor performance status
- Compromised organ function
- Previous significant toxicity
- Obese patients (use adjusted body weight)
When to Maintain Full Dose:
- Curative intent treatments
- Young, fit patients
- Agents with wide therapeutic index
Always individualize based on patient factors.
Q: What are the most important safety measures when preparing chemotherapy?
A: Critical safety measures include:
Personal Protective Equipment:
- Double gloves with powder-free inner glove
- Closed-front gown with elastic cuffs
- Eye protection when splashing possible
- N95 mask when handling powders
Environmental Controls:
- Biological safety cabinets
- Proper ventilation systems
- Spill kits readily available
- Segregated preparation area
Verification Process:
- Triple verification of dose calculation
- Independent pharmacist review
- Barcode scanning when available
- Clear labeling of all preparations