Pharmacokinetics and pharmacodynamics lectures Flashcards
Pharmacokinetics vs pharmacodynamics?
Kinetics: what the body does to the drug.
Dynamics: what the drug does to the body.
4 stages of pharmacokinetics:
Absorption, distribution, metabolism, excretion.
What is the area under the curve dependant on?
Amount in systemic circulation which is dependant on the amount administered and the rate of elimination.
What is fracton of dose âFâ mean?
How do you calculate it?
Explain ionisation of a weak base/weak acid drug?
What does this mean for absorption?
What are the main routes of clearance of a drug?
Explain volume of distribution?
Why is vd useful?
Volume of distribution: how well a drug is distributed through the body. The more compartments a drug gets to the higher the volume of distribution.
- Ab=amount of drug administered, Cp=concentation of drug in plasma.
How do you work out the loading dose?
How can Vd and Cl be used to figure out t1/2?
Phase 1 and phase 2 of of drug metabolism?
Phase 1: carried out by cytochrome p450s (CYPs)
What is the most important CYP enzyme?
Where is it found within cells?
Found on the endoplasmic reticulum
What are the major phase 2 enzymes?
What is the purpose of phase 2 enzymes?
Explain prodrugs and why they might be beneficial
Explain what a metabolic shunt is
Can create a toxic metabolite if the wrong pathway is used
Induction of CYP3A
Why can you not use grapefruit in a lot of cases?
