FB - Clinical Pharmacokinetics Flashcards
What is the primary goal of clinical pharmacokinetics in medicine?
Enhance drug efficacy, Reduce drug toxicity
What factors are considered in determining the appropriate loading dose of a drug?
Desired plasma drug concentration, Drug’s apparent volume of distribution
How does the timing of drug administration relate to trough plasma drug concentration?
Drugs should be administered after the trough level is reached to maintain effective concentration and minimize toxicity.
Why is patient age important in drug administration?
Age affects organ functions that impact drug metabolism and excretion, influencing drug dosage and frequency.
What is the significance of achieving a steady state in drug therapy?
Steady state indicates a balance between drug dosing and elimination, ensuring consistent therapeutic effects.
How does multiple dosing affect the plasma drug concentration?
Multiple dosing leads to drug accumulation until a steady state is reached.
What role does drug mechanism of action play in dosage regimen?
It determines how the drug interacts with the body, influencing efficacy and safety of the dosage regimen.
Why is patient compliance important in pharmacotherapy?
Non-compliance can lead to (a) suboptimal therapeutic outcomes and increased risk of drug resistance, (b) overdosing and increased drug toxicity.
How can drug toxicity be minimized in clinical practice?
By monitoring plasma drug levels and adjusting the dosage accordingly.
What is the importance of the apparent volume of distribution in pharmacokinetics?
It provides an idea where the drug is likely to be distributed in the body; helps in calculating the correct loading dose to achieve the desired drug concentration in the body.
How does renal function impact drug dosing and selection?
Renal impairment can reduce drug clearance, necessitating dosage adjustments to prevent toxicity.
What is the relevance of pharmacokinetic principles to personalized medicine?
They enable individualization of drug therapy based on patient-specific factors for optimal efficacy and safety.
After how many half-lives does a drug reach steady state with multiple dosing?
Steady state is reached after 5 half-lives (T½) of the drug.
How is dosing modified for drugs with different half-lives?
If T½ is 8-24 hours, dosing could be three to onetimes daily. If T½ is short (eg. less than 3 hours), intravenous (IV) infusion or sustained released preparations can be used.
For drugs with low therapeutic index (TI), what is crucial for optimum therapeutics?
Considerations for pharmacokinetics (PK) are more important in drugs with low TI and in patients with altered absorption, distribution, metabolism, and excretion (ADME).
