Classify weight status and get dosing-weight guidance for the patient's BMI category.
Pharmily+
BMI classifies a patient's weight status and tells you which weight to use for dosing — actual body weight isn't always the right choice once a patient is significantly over or under a healthy weight. See How Calculator Tools Work for the shared layout.
Use actual body weight. Monitor for drug toxicity — low volume of distribution.
18.5–24.9
Normal
Use actual body weight for standard dosing.
25–29.9
Overweight
Use actual body weight for most drugs; consider Ideal Body Weight for aminoglycosides.
30–34.9
Obese Class I
Consider Adjusted Body Weight for renally-cleared drugs.
35–39.9
Obese Class II
Use Adjusted Body Weight for renally-cleared drugs. Monitor drug levels where available.
≥ 40
Obese Class III (Morbid)
Drug distribution may be significantly altered — consult a clinical pharmacist for dosing guidance.
For the Adjusted Body Weight itself, use Ideal Body Weight (IBW), which calculates both IBW and AdjBW together.
A BMI outside 12–70 triggers a warning to double-check the weight and height you entered — that range is far outside normal clinical values and usually means a typo.