Session 5_Application of Pharmacokinetics to obese pts Flashcards
What is the primary objective of pharmacokinetics in obese patients?
To explain the differences in pharmacokinetics in obese versus non-obese patients.
What does the acronym BMI stand for?
Body Mass Index.
How is BMI calculated?
BMI = body weight (kg) / [height (m)]^2.
What is the classification of obesity based on BMI for ‘Obese’?
BMI of 30-39.9 kg/m².
What is the classification of obesity based on BMI for ‘Morbidly Obese’?
BMI of ≥40 kg/m².
What is the Ideal Body Weight (IBW) formula for males?
IBW = 50 kg + 2.3 kg for each inch over 5 feet.
What is the Ideal Body Weight (IBW) formula for females?
IBW = 45.5 kg + 2.3 kg for each inch over 5 feet.
What is Total Body Weight (TBW) in the context of obesity classification?
Measured body weight.
What is the impact of obesity on drug absorption?
Information on absorption and bioavailability of medications in obese patients is scarce and inconclusive.
What is the influence of lipophilicity on drug distribution in obese patients?
Lipophilic medications show a larger increased volume of distribution, while hydrophilic medications show less increase.
What is the effect of obesity on liver enzyme activity?
Phase I and Phase II enzyme activity is affected in obese patients.
Which enzyme activity is reduced in obese patients?
CYP3A4 activity.
What is a significant change in renal elimination for obese patients?
Higher clearance of drugs primarily eliminated by glomerular filtration.
What is the recommended weight to calculate loading doses for drugs distributed in lean mass?
Ideal Body Weight (IBW).
What is the recommended weight to calculate loading doses for drugs distributed in fat tissues?
Total Body Weight (TBW).
What equations are commonly used to estimate glomerular filtration rate (GFR)?
- Cockcroft-Gault (CG) equation
- Modification of Diet in Renal Disease (MDRD) equation.
What is the Cockcroft-Gault equation used for?
To estimate creatinine clearance (Clcr) as a surrogate of GFR.
What is the formula for the MDRD equation developed in 1999?
eGFR = 186 x (sCr)^-1.154 x (age)^-0.203 x 0.742 (if female) or x 1.212 (if black).
What weight should be used to estimate Clcr for overweight or obese patients?
Adjusted Body Weight.
What is the formula for calculating Adjusted Body Weight?
Adj. BW = IBW + 0.4 × (TBW - IBW).
What is the BMI of a patient weighing 350 lb and 5 feet 5 inches tall?
58.4 kg/m².
What is the significance of individualized therapeutic drug monitoring in obese patients?
It is warranted due to inter-individual variations within the obese population.
True or False: The distribution of hydrophilic medications is less affected in obese patients compared to lipophilic medications.
True.
Fill in the blank: The prevalence of ______ has increased substantially worldwide in recent years.
obesity.
What medical conditions are associated with obesity?
- Diabetes
- Hypertension
- High cholesterol
- Stroke
- Heart disease
- Certain cancers
- Arthritis.
What is a significant finding regarding tubular secretion in obese patients?
Higher tubular secretion for procainamide, ciprofloxacin, and cisplatin.
What is the conclusion regarding drug dosing for obese patients?
Applying pharmacokinetic principles and using modified weight strategies may help with better drug dosing.
