PHARMACOLOGY Flashcards
Drug disposition commences with which of tge following pharmacokinetic principles?
A. Absorption
B. Distribution
C. Metabolism
D. Excretion
DISTRIBUTION
Disposition: DME
Pharmacokinetics: ADME
Drug EliMInation: ME
Drug elimination commences with which of the following pharmacokinetic process?
A. Absorption
B. Distribution
C. Metabolism
D. Excretion
METABOLISM
Drug Disposition= Drug Dstribution
Drug Elimination= MEtabolism
EliMination: ME
True of bioavailability
A. Rate and extent of drug distribution
B. Amount of drug in the blood stream
C. Rate and extent of drug clearance
D. 10% only for IM administered
AMOUNT OF DRUG IN THE BLOODSTREAM
Rate and extent on DRUG ABSORPTION
90% bioavailability IM
10% bioavailablity topical
True of bioavailability
A. Applicable only to IV drugs
B. Reflects fraction of drugs metabolized
C. Always poor in orally administered drugs
D. Greatly affected by drug absorption
GREATLY AFFECTED BY DRUG ABSORPTION
Bioavailability= durgs absorbed/ in blood stream
Oral drugs have LESS biovailability, not poor
!!Beware ALWAYS and ONLY words!!
Which of the following statements is correct:
In IV Route…
A. Drugs NOT absorbed, 100% bioavailability
B. Compared to Oral drugs which are poorly absorbed with 100% biovailability
C. Good absorption, 100% bioavailability
D. Depot effect
IV drugs ARE NOT ABSORBED because they go DIRECTLY blood stream. There is no LOSS od the drug.
Patient ingested 24 Aspirin tablets and developed hepatic encephalopathy. Blood needs to be alkalanized via IV NaHCO3. What is the basis of this management?
A. NaHCO3 traps aspirin in ionized form
B. NaHCO3 neutralizes free aspirin in the systemic circulation
C. NaHCO3 increases fraction of protein bound aspirin, reducing toxicity
D. NaHCO3 induces CYP450 enzyme in hepatocytes, accelerating elimination of the toxin
NaHCO3 TRAPS ASPIRIN IN IONIZED FORM
“Ionized trapping” based on Henderson Hassleback Equation, acid+basic –> ionized form –> excreted
EXCRETABLE: ionized/ non-lipid soluble/ polar (I NL P)
ABSORBABLE: non-ionized/ lipid soluble/ non-polar (non-lipd-non)
In a case of sepsis, prompt antibiotic administration is needed. In these cases, a loading dose would be warranted. What is the basis for the computation of the loading dose?
A. Drug plasma concentration
B. eGFR and serum creatinine
C. Drug clearance
D. Volume distribution of a drug
VOLUME DISTRIBUTION OF A DRUG
amount of drug into tissue/body fluid
Phenobarbital was given to a patient on chronic warfarin. It is classified as:
A. Pharmacodynamic antagonist
B. Pharmacokinetic antagonist
C. Physiologic antagonist
D. Chemical antagonist
PHARMACOKINETIC ANTAGONIST
Phenobarbital is an ENZYME EINDUCER hece affects METABOLISM
Pharmacologic drugs that has noth INTRINSIC ACTIVITY and AFFINITY:
A. Agonist
B. Antagonist
C. Synergist
D. None
AGONIST
Intrinsic activity- binding; leads to pharmacologic response
Affinity- ability to bind to a receptor; fits
Pharmacologic drugs that has AFFINITY but NO INTRINSIC ACTIVITY:
A. Agonist
B. Antagonist
C. Synergist
D. None
ANTAGONIST
Intrinsic activity- binding; leads to pharmacologic response
Affinity- ability to bind to a receptor; fits
Which of the following drugs has a narrow therapeutic window?
A. Diazepam
B. Aspirin
C. Digoxin
D. Bethacolol
DIGOXIN
Narrow therapeutic index drugs: WALA C PhePhe! VAs-THE-D!
Warfarin, Aminoglicosides, Lithium, Ampothericin B, Carbamazepine, PHEnytoin, PHEnobarbital, VAncomycin, THEophylline, Digoxin
How many half lives needed to reach a steady state?
A. 2-3
B. 3-4
C. 4-5
D. 5-6
3-4 half lives to reach a steady state
Patient has acute live failure and is given Drug A which is a protein bound drug. Which of the following is true?
A. The drug will have no effect on patient
B. The drug will have a toxic effect on patient
C. The drug will have an enhanced effect on the patient
D. The drug will not be metabolized
The drug will have increased TOXICITY
Patient with liver disease is likely to have HYPOALBUMINEMIA.
Prontein= binds, not cross biomembranes= NO EFFECT, NOT EXCRETED
Low albumin= less protein= less binding= more effect/ toxicity
A target plasma theophylline concentration of 10mg/L is desired to relieve acute bronchial asthma in a patient. If the patient is a nonsmoker and otherwise normal except for asthma, mean clearance is 2.8L/hr. The drug is to be given as an IV infusion dosing interval is 12hrs. Determine the DOSING RATE and MAINTENANCE RATE.
Maintenance rate= Dosing rate x dosing interval (MR DR DI)
Dosing rate= Target conc x Clearance (DR TC)
What is the preferred reliever across all steps in the stepwise approach in asthma management?
A. LABA
B. SABA
C. Methylxanthine
D. ICS+ Formoterol
ICS + Formoterol
Previously SABA due to ecenomic reasons but changed due to “SABA only treatment”. Inc in SABA= Dec in B2 receptors= reduced effectivity
