Pharmacokinetics studying Flashcards
Differentiate between first order and zero order kinetics
1) First-order (linear) kinetics: a constantfractionof drug is eliminated per unit time (most drugs)
2) Zero-order (nonlinear) kinetics:
a constantamountof drug is eliminated per unit time
~97% of a drug will be cleared at ____ half-lives, which is at steady state
5
What is the 5 half life rule?
5 half-lives to reach steady state, 5 half lives for elimination
Steady state is achieved during initiation of a therapy after ∼5 elimination half-lives, or _____ doses.
10
Measuring the concentration of a drug or its metabolite for the purpose of therapy is what?
Therapeutic Drug Monitoring (TDM)
Samples for TDM are often collected at a specific time related to dosing; usually measured as _______ (just prior to next dose) or _______ levels (timing depends on drug, e.g., 30-60 minutes after dose)
trough; peak
Drug of Abuse Testing (DAT) is commonly done via what?
Urine drug screen (UDS)
Is Drug of Abuse Testing (DAT) quantitative or qualitative?
Qualitative
What may cause false+ opiate DAT?
Quinolone antibiotics (e.g., levofloxacin)
Decongestants can cause you to test positive for what?
Amphetamines
What 2 drugs don’t have any false-positive causing agents?
Cocaine and THC
What may cause you to test positive for PCP? (phencyclidine)
Dextromethorphan and diphenhydramine
Is cocaine drug testing sensitive or specific?
Specific
You can measure Carbon monoxide (CO) by what?
Carboxyhemoglobin (COHb) using blood gas co-охimеtry
Serum cholinesterase enzyme activity is inhibited with what poisoning?
Insecticides (organophosphates)
How do you measure lead?
Whole blood lead level
