Lect1: Class activity Flashcards
Intro of PK
Identify PK
- a metabolic enzyme’s effect on a certain drug
- how long a drug stays in the body
Identify PD
- a certain drug’s effect on a metabolic enzyme
- the activity of a drug in the body
In a study, researchers determined the drug concentration at the site of action and the resulting pharmacological response. The main aim of the study was to determine if a relationship existed between the drug concentration and the pharmacological response. This study is an example of:
a pharmacodynamic study
A patient was given an oral dose of Tylenol for his sore throat. He might ask “How will the drug get from mouth to my sore throat”? If you were the pharmacist, what would be your answer?
The drug is absorbed into the bloodstream through the stomach and intestines, then carried to different parts of the body, including the throat to reduce inflammation and pain.
Drug distribution:
- is a process by which the drug reaches it site of action
- after drug entry into the systemic circulation, drug reaches other tissues by distribution
True or false:
Once a drug is distributed to different tissues, it cannot re-enter the systemic circulation?
False
True or false:
Distribution is the process by which a drug is permanently removed from the body?
False; elimination
Drug eliminaton:
- removal of drugs from the body
- includes both drug excretion and metabolism
- is (generally) an irreversible process
The study of drug distribution and elimination is called?
pharmacokinetics (PK)
Measurement of drug concentration is:
the concentration of a drug at the target site that is related to drug response
MEC and MTC
MEC: minimum effective concentration
MTC: minimum toxic concentration
Cmax:
peak concentration level
Tmax:
time for Cmax
Onset time:
time to reach MEC
Duration:
difference between onset time and time for the drug to decline back to MEC
Which of the following statement is/are true about compartment models:
- different organs that have similar drug distribution are group together into one compartment
- the drug is considered to be uniformly distributed within the compartment
- drug can be eliminated from a compartment model
- mixing of the drug within the compartment is considered instantaneous
- faster the drug distribution process, lesser is the number of compartments needed to describe the plasma concentration time profile of a drug
What are the assumptions for a one-compartment model?
- the entire body acts as a single compartment
- the drug rapidly equilibrates with all of the tissues in the body
- first order elimination
Higher clearance leads to:
lower plasma concentrations
Rate of elimination equation is
RE= CL * C
Clinical trials:
- phase II determines drug pharmacokinetics
- phase II determines dose range
- phase I determines safe dose range
- phase III determines efficacy
- a drug can get approved w/out a phase IV trial
It is important for a pharmacist to keep up w/ possible label revision in a drug newly approved. What could be the mostly possible reason?
warning and precautions
