Individual Variation in Drug Responses

Question 1

4 pathologic conditions that have profound effect on individual drug variations:

Answer 1

1) kidney disease
2) liver disease
3) acid-base imbalance
4) altered electrolytes

Question 2

tolerance

Answer 2

decreased responsiveness to a drug as a result of repeated drug administration

Question 3

pharmacodynamic tolerance:

Answer 3

assoc with long-term administration of drugs (morphine, heroin etc.)
result of adaptive processes that occur in response to chronic receptor occupation

Question 4

metabolic tolerance:

Answer 4

resulting from accelerated drug metabolism; barbiturates; induce the synthesis of hepatic drug-metabolizing enzymes thereby causing rates of drug metabolism to increase

dosage must be increased to maintain therapeutic drug levels

*metabolic tolerance does not effect MEC

Question 5

tachyphylaxis

Answer 5

reduction in drug responsiveness brought on by repeated dosing over a short time
example: nitroglycerin patch becomes ineffective if left on continuously

Question 6

placebo effect

Answer 6

can be beneficial or negative

Question 7

bioavailability

Answer 7

the amount of an active drug that reaches the systemic circulation from its site of administration

Question 8

things that alter bioavailability

Answer 8

tablet disintegration time, enteric coatings, sustained-release formulations

Question 9

individual causes of variable absorption

Answer 9

gastric pH, diarrhea can reduce, constipation can enhance

Question 10

differences between men and women

Answer 10

dig increases mortality in women
ETOH is metabolized more slowly by women
some opioids are much more effective in women so their MEC is lower for men
quinidine causes greater QT prolongation in women than men

Question 11

consideration for black patients

Answer 11

isosorbide dinitrate and hydrazine decreased mortality by 43%