Adaption to drugs: tolerance, sensitization and expectation (Ch3)

Question 1

Tolerance

Answer 1

A decrease in drug effect with repeated administration of the same dose or an increase in does required to produce and effect as intense as one produced by the initial dose. Right shift on DRC. Different effects develop tolerance at different rates

Question 2

Acute tolerance

Answer 2

tolerance within a single administration. The effect of a drug at a given blood level is greater when the drug level is rising than when falling.

Question 3

Mechanisms of tolerance (2)

Answer 3

1) pharmacokinetic (metabolic/dispositional)
2) pharmacodynamic (physiological/cellular)

Question 4

Pharmacokinetic (metabolic/dispositional) tolerance

Answer 4

A decrease in effect as body becomes more efficient at metabolizing and excreting the drug; less drug reaches site of action. Diminishes ALL effects of a drug.

Question 5

Pharmacodynamic (physiological/cellular) tolerance

Answer 5

Repeated exosure to the drug initiates homeostatic processes that work to restore normal functioning. At the cellular level, there is down regulation, ora decrease in effect that stimulates receptors by decreasing receptor affinity or decreasing the number of receptors

Question 6

Functional disturbances

Answer 6

Tolerance develops when drugs cause disruption in homeostasis that has significant consequences for the organism. Ex: Amphetamine makes you want to not eat. No tolerance developed if animals are administered drug when hungry and no food is present. Tolerance requires food to be present and hunger to be present.

Question 7

Behavioural tolerance

Answer 7

the organism learns to function under the influence of a drug

Question 8

Conditioned tolerance

Answer 8

tolerance occurs in the same environment in which the drug was administered, but is absent/reduced in novel environments.

Question 9

Withdrawal

Answer 9

Symptoms that occur when drug use is stopped, dose reduced, or antagonist is given

Question 10

What are withdrawal symptoms

Answer 10

the opposite of the drug effect (nervous system adjusts to the absence of the drug). CNS depressants produce withdrawal syndrome characterized by CNS hyper excitability. CNS stimulants do the opposite.

Question 11

Dependence

Answer 11

Does not equal addition, but depends on usage. One is not necessarily dependent if discontinuing the drug leads to withdrawal or if they compulsively use the drug to avoid withdrawal. This is because you can show withdrawal without compulsive use or show compulsive use without withdrawal. The current approach is based on self administration.

Question 12

Opponent process model

Answer 12

a process (initial, pleasurable state) followed by a B process (compensatory, unpleasant). B cancels out A. B lasts longer. When A ends, B dominates (withdrawal). Repeated use: B process intensifies, begins sooner, lasts longer. Get around this by upping the dose. The A effect stays the same with dose . Pleasurable effect might develop tolerance, but the effect that could kill you doesn’t develop tolerance.

Question 13

Hangover

Answer 13

brief period of withdrawal symptoms arise form acute tolerance

Question 14

Alcohol A and B processes

Answer 14

A - muscular relaxation, tolerance of noise and bright lights, analgesia, analytic, euphoria. B process = opposite

Question 15

Respondent conditioning of drug effect

Answer 15

The stimuli present just prior to drug administration predict the occurrence of the drug. Repeatedly pairing stimuli. (CS —> CR and CR is drug like)

Question 16

Respondent conditioning of compensatory effect (CCR)

Answer 16

CS —-> CR and CR is drug opposite effect
- if in the presence of a drug, this will lead to tolerance
- if in the absence of a drug, this will lead to cravings and withdrawal symptoms

Question 17

Siegel, Hinson and Krank - Illustrative experiment

Answer 17

3 groups - different, same and control. 96% control dead, 64% of different dead, 32% of same dead. No CCR in different group.

Question 18

Conditioned withdrawal

Answer 18

paired tone/odour CS with drug. CS presented with saline injection = withdrawal symptoms