1. What is mg/m² Dosing?

mg/m² dosing is a method of calculating medication doses based on body surface area (BSA), commonly used for chemotherapy drugs and other medications where precise dosing is critical. This method often provides better dose individualization than weight-based dosing.

2. How Does the Calculator Work?

The calculator uses the simple formula:

Where:

• \( D_{m2} \) — Dose per square meter of body surface area (mg/m²)
• \( BSA \) — Body surface area calculated using Mosteller, DuBois, or other formulas (m²)

Explanation: This calculation adjusts the medication dose according to the patient's body size, which often correlates better with metabolic rate and drug clearance than body weight alone.

3. Importance of BSA-based Dosing

Details: BSA-based dosing is particularly important for medications with narrow therapeutic windows, where both underdosing and overdosing can have serious consequences. It's widely used in oncology, pediatrics, and for certain antibiotics.

4. Using the Calculator

Tips: Enter the prescribed dose per m² (typically found in drug references) and the patient's calculated BSA (from Mosteller or other formulas). Both values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: Why use BSA instead of weight for dosing?
A: BSA often correlates better with metabolic rate and drug clearance than weight alone, especially for drugs that distribute in body water or metabolize in the liver.

Q2: How is BSA calculated?
A: Common formulas include Mosteller (√[height(cm)×weight(kg)/3600]) and DuBois. Many electronic medical records automatically calculate BSA.

Q3: When is mg/m² dosing typically used?
A: Primarily for chemotherapy, some antibiotics (like amphotericin B), and medications with narrow therapeutic windows.

Q4: Are there limitations to BSA dosing?
A: It may be less accurate in obese patients, and some drugs require additional adjustments (like ideal body weight calculations).

Q5: Should BSA dosing be used for all medications?
A: No, only for medications specifically dosed this way. Many drugs use weight-based (mg/kg) or fixed dosing.