Chapter 3: How We Adapt to Drugs- Tolerance, Sensitization, and Expectation

drug tolerance

decreased effectiveness or potency of a drug that results with repeated administrations, or as the necessity of increasing the dose of a drug in order to maintain its effectiveness after repeated administrations

cross-tolerance

a condition in which the development of tolerance for one drug causes an individual to develop tolerance for another drug

acute tolerance

tolerance that has developed during a single administration

pharmacokinetic tolerance

develops when the ability to metabolize or excrete the drug increases over time, resulting in fewer drug molecules reaching their sites of action

pharmacodynamic tolerance

tolerance caused by altered nervous system sensitivity; adjustments made by the body to compensate for an effect caused by the continued presence of a drug

upregulation

increase in receptor-site sensitivity to a neurotransmitter or an increase in the synthesis and release of a neurotransmitter

downregulation

decrease in receptor-site sensitivity to a neurotransmitter or a decrease in the synthesis and release of a neurotransmitter

behavioural tolerance

can be influenced by learning; through experience with a drug, an organism can learn to decrease the effect that the drug is having

withdrawal symptoms

physiological changes that occur when the use of a drug is stopped or the dosage is decreased

cross dependence

dependence on a drug can be relieved by drugs of the same family with similar mechanisms

dependence

a state in which discontinuation of a drug causes withdrawal symptms

addiction

a state in which a person compulsively takes a drug

hangover

usually refers to the aftermath of the acute effects of a drug, such as when you go out drinking and then feel sick the next day

letdown

a period of depression that can be thought of as a compensatory response to the high caused by the drug

anxiolytic

a drug that relieves anxiety and has a calming effect

anxiogenic

a drug that causes tension and anxiety

hyperalgesia

increased sensitivity to pain

conditional tolerance

tolerance to a drug only in an environment where the drug has been experienced before

sensitization

certain effects of a drug increasing with repeated administration

stereotyped behaviours

invariable, repetitive movements, such as head bobbing and sniffing, which are engaged in for extended periods of time and appear to have no purpose

cross sensitization

the use of one drug produces sensitization in the response to another drug

nocebo effect

negative expectations from treatment outcome result in negative outcomes