Addiction Day Flashcards
(44 cards)
explain the neurobiology of addiction
chronic, progressive behavioral disorder whose central feature is compulsive drug use despite adverse consequences
-pathophysiology involves brain reward system and alterations that reward enhancing drugs effect on this system
how is the ventral tegmental area involved in addiction?
location of dopamine cell bodies that projects to nucleus accumbens (reward center) and prefrontal cortex (executive control)
-dopamine is made and stored here (barn)
how is the nucleus accumbens area involved in addiction
“reward center” of the brain
- integrates VTA (dopamine) and PFC (glutamate) inputs to determine motivational output
- -incentive (appetite)
- -reward (consummatory)
- excitement (horses)
how is the prefrontal cortex involved in addiction?
exerts executive control over midbrain structures
- judgement
- cost-benefit analysis
- consider further PFC delination next
- “rein in” excitement (wranglers)
how are the DLPFC, VMPFC, OFC, and ACC involved in addiction?
DLPFC: statistical analysis, prioritizing, top-down control center –> failure to assess risks of a behavior)
VMPFC: assigns emotional valiance –> drinking feels good, less stress, more social
OFC: impulse prevention –> can beat up, grope, or drive w/o consequence
ACC: vigilance –> scanning environment for next hit
decision making is done via?
glutamate driven via PFC structures
what is limbic drive due to?
dopamine driven
- D3 receptors govern static levels of DA neuronal activity to allow homeostatic wakefulness, alertness, etc.
- D2 receptors are pulsatile depending on motivation, derive, reward expectations, etc
what does chronic use of drugs lead to?
reward circuitry changes that promote more future drug use
- increased limbic function
- decreased PFC function
how does the limbic drive actually work? in addiction?
- VTA barn supplies DA to the nucleus accumbens
- NA receives input and chooses which horse to use
- amygdala assigns a pleasure, threat, or emotional value to linkage between 1 and 2
- 1 through 3 are limbic addiction pathways that are excessive in addictive behavior
how does cortical control actually work? in addiction?
- OBF should suppress doing dangerous or addictive things
- VMPFC should attach positive feelings to not doing dangerous things
- DLPFC should calculate true risk/benefit ratio of doing addictive things
- this system is overridden in addiction
what happens to frontal lobe structures in addiction?
become less active due to less glutamate
-may even atrophy, allowing increasing, maladaptive addictive (more DA) behaviors to occur
what does alcohol intoxication look like? Rx?
- anxiolysis
- dishinbition
- slurred speech
- ataxia
- sedation/stupor
- respiratory suppression
- coma
- death
Rx: support, restraint, protect airway, ventilate
what does alcohol withdrawal look like? Rx?
- agitation
- insomnia
- tremor
- GI upset
- increased pulse, HR, BP
- seizures
- hallucinations
- delirium
- death
Rx: benzodiazepines (X-reactive) until vital signs and withdrawal symptoms normalize
what does benzodiazepine or barbiturates intoxication look like? Rx?
- anxiolysis
- slurred speech
- ataxia
- sedation/stupor
- respiratory suppression
- coma
- death
Rx: support, restraint, protect airway, ventilate
-reverse with flumazenil for benzodiazepines, but may cause seizures
what does benzodiazepine or barbiturate withdrawal look like? Rx?
- agitation, insomnia
- tremor
- GI cramps
- hypereflexia
- increased HR
- seizures
- hallucinations
- delirium
- death
Rx: benzodiazepine replacement until vital signs and withdrawal symptoms normalize
what do stimulants do to D2?
block dopamine reuptake, may reverse it
-more DA availability in mesolimbic system allows increased CNS arousal and excitability
what does stimulant intoxication look like? Rx?
- elevated mood/esteem
- irritability
- insomnia
- appetite loss
- dilated pupils
- racing heart
- increased BP, elevated temperature
- hyperreflexia
- psychosis
- cardiac arrest due to hypoxic brain injury
- seizure
Rx: support, use meds to reverse specific intoxication symptoms
what does stimulant withdrawal look like? Rx?
- fatigue
- anhedonia
- depression
- increased sleep (crash) or decreased sleep
- increased appetite
Rx: slowly stimulate D uptake
what exactly is an opiod and where does it bind?
opiods are anything that bind and occupy receptors in the brain, exerting certain activities
what are the receptors affected by opiates? what do these cause?
- Mu (OP3, MOP) reduce pain, increase positive emotion
- Kappa (OP2, KOP), delta (OP1, DOP) allow mild analgesia
- -GPCR, causing neuronal hyperpolarization via cAMP reduction and increased K+ influx and decrease Ca++ efflux
- -increase descending midbrain pain inhibitory paths –> increase serotonin and enkephalin firing
what are many prescription narcotic pain meds?
naturally occuring alkaloids (poppy) or synthetic
-activate Mu, OP3, MOP receptors to control pain and improve emotional state associated with said pain
what does opiate intoxication look like? Rx?
- elevated mood
- pupil constriction
- respiratory suppression=gag reflex loss
- low HR, BP
- constipation
Rx: support, protect airway and use naloxone to reverse
what does opiate withdrawal look like? Rx?
- restless/agitated
- watery eyes
- yawning
- dilated pupils
- goose flesh/flushing
- runny nose/sneezing
- increased HR and BP
- GI distress
- GI cramps
- muscle craps
Rx: methadrone (full agonist replacement) or buprenorphine (partial agonist replacement)
what are hallucinogens?
PCP (phencyclidine), LSD (lysergic acid), mescaline, peyote, psilocybin
