CONDITIONS THAT IMPACT PK/PD TERMS A Flashcards
an alternative form of a gene at a given locus
allele
a segment of DNA sequences that is transcribed into mRNA and translated into proteins
coding region
the complete DNA sequence of an organism (the entire genetic makeup)
genome
a segment of DNA sequences that do not encode proteins
noncoding region
the study of genetic factors that underlie variation in drug response
pharmacogenomics
genes that encode drug metabolizing enzymes, drug transport molecules, molecular targets
genetic factors
need for unexpectedly high dose for usual effect
hyporeactivity
need less drug for usual effect
-jot confused with hypersensitivity
hyper reactivity
unpredicted reaction, not dependent on drug dosage, observed in small number of patients
- not an allergy
- examples: sulfonamides, phenytoin
idiosyncratic
hyporeactivity due to prior exposure to drug
tolerance
the compulsive need of an individual to use a drug to function normally
dependence
tolerance that quickly develops over a few doses which may be due to:
- all spare receptors may be filled
- structural changes in the receptors
- increased metabolism
- down reg of the receptors
tachyphylaxis
name this genetic variant:
a single nucleotide polymorphism that codes for the same amino acid when read out; DNA differs, but no change of function results
synonymous
name this genetic variant:
a SNP that results in substitution of a different amino acid when read out; a change in function may result
non synonymous
this is a genetic variant that is an insertion or deletion and can also alter protein function
indels
this is an increase in the amount of DNA in a specific region of the chromosome
gene amplification
5-10% of European and African derived populations are poor metabolizers
CYP2D6
20% of Asians are poor metabolizers of this genetic variant?
CYP2C19
PM have higher exposure to the active drug
shown to have improved treatment outcomes in treating gastric ulcer
proton pump inhibitor
omeprazole
requires CYP2C19 to form the active metabolite (bioactivation)
PM have been shown to have increased rates of MI (after coronary stent placement)
antiplatelet
clopidogrel
warfarin is metabolized by this genetic variant?
CYP2C9
most common enzymopathy worldwide, 400 million people
causes RBCs to break down prematurely leading to hemolytic anemia
-patients present with yellowing of skin
i.e. primaquine must be avoided because its associated with hemolysis in G6PD deficient patients
G6PD deficiency
this protein inactivates 6-MP which is the active metabolite of azathioprine (immunosuppressant)
thiopurine S-methytransferase
most commonly prescribed medication for asthma
homozygotes for Arg16 allele higher incidence of tachyphylaxis with regular albuterol use
beta-agonists (albuterol)
mutations on the ryanodine receptor on the sarcoplasmic reticulum in skeletal muscle cells
inhaled anesthetic gases or succinylcholine
- sustained muscle contraction
- hyperthermia, tachycardia, hypoxemia, tachypnea, hyperkalemia
treatment: dantrolene
malignant hyperthermia
name this genetic allele
chemotherapeutic (colorectal, lung, gastric, gynecologic)\
this activates an active metabolite of irinotecan
patients with this are at increased risk of severe toxicities like neutropenia, diarrhea
FDA recommends lower starting dose for this
UGT1A1
name this genetic allele
encodes for P-glycoprotein, widely distributed transporter protein
P-glycoprotein is an efflux pump
increased expression is _____
decreased expression is _____
ABCB1
more drug removal
less drug removal
what age is considered elderly?
65 yrs of age and older
