1 - Intro Flashcards
premises in drugs of abuse
- drugs are not good or bad
- every drug is pleiotropic therefore it affects more than 1 characteristic in the body
- drug effects depend on the amount of drug taken, the history, and expectation
drug schedules
drugs are sorted into five categories based on their abuse and dependancy potential
schedule 1 Drugs
- heroin, methamphetamine, morphine
schedule 2 Drugs
- nabilone, parahexyl, indole/pyrrole alkaloids
schedule 3 Drugs
- LSD, psilocybin, mescaline
schedule 4 Drugs
- barbiturates, benzos, catha edulis
schedule 5 Drugs
- propylhexedrine, pyrovalerone
schedule 6-10 Drugs
- precursors and solvents
- acetone, ether, lysergic acid, pseudoephedrine
sociopolitical anti-drug landscape changes
- war on drugs appear to be easing due legalization (including global legalization of narcotics)
- drug use is increasing across the globe
- poor and rich families are both vulnerable to addiction
addiction
- most pervasive form of dependence
5 C’s for addiction
Continued Compulsive Consequential out of Control use and Craving
how many points in criteria is needed for someone to be diagnosed as addicted?
2
pharmalogical concepts in drugs of abuse
- ADME
- cellular actions of drugs and neurotransmission
- acute and chronic effects in the CNS and periphery
- addiction effects (behaviour of individual and its social impacts)
- common characteristics of drugs of abuse (psychoactive)
ADME
Absorption (ingestion, inhalation, injection, insufflation)
Distribution (bioavailability, storage in the body)
Metabolism (through liver, kidney, spleen)
Excretion (through kidney, intestines, sweat glands, lungs)
drug-receptor interactions
without drug-receptor interactions, there’s no effect on the body
neurotransmission
- storage of neurotransmitter
- action potential
- results in the influx of calcium ions into terminal
- results in the exocytic release of neurotransmitter to the synapse
- neurotransmitters will bind to post-synaptic receptors
- trigger the post-synaptic cell resulting in depolarization or hyperpolarization
- reuptake or degradation of the neurotransmitters
process of addiction
reinforcement > tolerance > withdrawl > dependence > addiction
reinforcement
conditioning a stimulant with a reward
tolerance
- needing to take more of the drug/substance to feel the same effect
- taking more drug without feeling the effects
withdrawl
- opposite of the drug effect
- due to tolerance adaptations
- use of drug/substance is prolonged to avoid these unpleasant effects
dependence
- physical and/or psychological symptoms when drug is absent
- inability to function normally without the drug
stimulant drug effects
- neural activity increases when drug enters the body
- membrane will decrease/remove receptors allowing return of normal activity
- there is now less receptors in the membrane, therefore when the drug is absent, there is a decrease in neural activity than before
sedative drug effects
- neural activity decreases when drug enters the body
- membrane will increase/add receptors allowing return of normal activity
- there is now more receptors in the membrane, therefore when the drug is absent, there is an increase in neural activity than before (overstimulation)
addiction cycle
addiction is a cycle binge-withdrawl-anticipation
binge/intoxication
- affects the basal ganglia
- integrates motivational and executive circuits
- fires dopamine reward network, therefore it feels really good
withdrawl/negative effect
- affects the extended amygdala
- rewards lose motivational power, therefore a high enough reward is only given when the drug is present in the body
- elevated dopamine in reward causes stress, dysphoria, in amygdala “anti-reward” network without the drug
- therefore, users will want to continue drug intake to avoid dysphoria
anticipation
- affects the prefrontal cortex
- controls executive function, self-reg, decision making, error monitoring
- drug will impair dopamine and glutamate transmission
- cannot resist strong urges
- poor decision making
drug effects outside the CNS
- cocaine burns out heart tissue
- smoking causes cancer
