Drug tolerance
what is acute tolerance?
building tolerance to a drug after the first administration
what is up-regulation?
cell membrane increases production of receptors, and synthesis and release of neurotransmitters
what is one psychological effect of the opponent process theory?
conditioning
what is a side effect of sensitization?
damage to brain tissue
what is tolerance?
decreased effectiveness of a drug due to repetitive administration, or maintaining effectiveness of the drug by repetitive administrations
whats the difference between terms: "dependant" and "addiction" ?
dependance is a reliance to the drug in order to denote a physiological requirement to maintain homeostasis. whereas addiction is the action to denote a psychological want, not required for homeostasis
what is sensitization?
reverse tolerance; increased response to drug, despite prolonged use
when are the feelings of euphoria the highest? what is this called?
right after using the drug; acute tolerance
what does behavioural tolerance depend on?
self awareness and determination
what is cross tolerance?
when you build tolerance to another drug within the same drug family (i.e. tolerance to heroin will cause tolerance in morphine)
what is the compensatory response equivalent to?
withdrawal symptoms
how does the physiological response work in regards to cross tolerance? (2)
1. down regulation of receptors affects neurotransmission of all transmitters at that receptor 2. plateau in the reward-feedback system (less dopamine)
what does pharmacokinetic tolerance increase the rates of ? (3)
1. enzyme specific proliferation 2. elimination from body 3. induces cross tolerance
whats the problem with 1. and 2.?
1. may potentially harm similar substrates 2. zero order elimination induces stress
what are the two main biological effects of the opponent process theory?
1. the drug effect (euphoria) 2. body's compensatory response (dysphoria)
What is mithradatism?
Another word for tolerance
What is the diathesis stress model?
Model shows how behaviour can be influenced by both genetic and environmental factors
what is down regulation?
When the cell membrane decreases productions of receptors, and decreases synthesis and release of neurotransmitters
describe acute tolerance
actue tolerance happens when the drug's effect is much greater at time A then time B, even though the blood levels at both times are the same
what is tachyphylaxis?
acute tolerance
what is cross dependance?
another drug from the same family, when administered, can stop the withdrawal symptoms of the other drug which caused the withdrawal symptoms in the first place
what happens when a drug over stimulates receptors of the cell?
down-regulation
what happens when a drug keeps repeatedly gets administered in regards to the opponent process theory? what is the end result?
dysphoria will kick in sooner, be more intense, and last longer, which diminishes the euphoric state; increased tolerance
how does the metabolism of cross tolerance function?
enzymes respond to specific sections of molecules, thus similar chemical structure results in deactivation
what are protective factors?
factors that can protect us from environmental stress such as relationships, exercise, mental health, etc
what are some problems with the opponent process theory
i. doesn't differentiate between zero vs first order rxn ii.. can't explain tachyphylaxis iii. doesn't take into account drugs that don't produce withdrawal
amphetamine causes anorexia in rats, however if there is no presented while rat is administered amphetamine, why does it not cause anorexia?
if there is no food, amphetamine would not function to change homeostatic state of rate. therefore, tolerance will develop only where a drug places a demand on the organisms homeostatic organism
is behavioural tolerance a true tolerance?
no; because it is a mind state
the _______ of receptors may change, but not the ________ _______?
number; receptor sensitivity
what is cell adaptation theory in regards to pharmacodynamic tolerance?
once a drug has been introduced to the body, the body attempts to obtain a state of balance (homeostasis) to compensate for the drug's effects. Therefore, when a drug is administered frequently, it trains the body to becomes more efficient at returning back to homeostasis aka tolerance
what is selective tolerance?
one effect is diminished, but the other is not
what is functional tolerance?
pharmacodynamic tolerances
what is dispositional tolerance?
pharmacokinetic tolerance
what is pharmacodynamic tolerance?
physiological adjustments made to compensate for an effect by a drug
what is withdrawal symptoms?
physiological changes that occur when the drug has been stopped being administered
What is dependance?
refer to slides (not a clue) - ask ben
what can tolerance result from?
repeated exposure that affects physiology
compensatory response is not a _______, but a ________; why is this?
response; state. this is because the state of pleasure is temporary, but the physiological changes (compensatory response) is somewhat permanent
what is behavioural tolerance?
the adjustments and compensation of a drug as a result of experience
why does this dysphoria occur after euphoria?
the body has to maintain homeostasis, thereby responds to the drug effects
what is stress?
the environmental event that disrupts equilibrium
what is diathesis?
the genetic factor of having the predisposition to be vulnerable to the environment
what is pharmacokinetic tolerances?
the increase ability of the body to metabolize the drug, resulting in fewer molecules to reach receptor site (essentially destroying the drug)
What is the opponent process theory?
the theory states that: every process is followed by a secondary opponent (opposite) process. in other words, it explains why after extensive administration of a drug, the body will go through physiological changes to compensate when the drug wears off, which causes withdrawal symptoms
what happens, physiologically, when the drug blocks the receptors of a cell in an attempt to compensate for this situation?
up-regulation
