Flashcards
Drugs of abuse
Cards in this deck (14)
- 1What is drug dependence?State (psychological &/or physical), resulting from interaction between drug & organism, characterized by a compulsion (periodic/continuous) to experience psychic effects &/or avoid discomfort of withdrawal
- 21. Which drugs cause psychological dependence (wish, need, desire, craving)? 2. Which cause physical withdrawal?1. All drugs
2. Only depressant drugs (opioids, alcohol) - 3What r major classes of drugs? Give examplesDepressants: alcohol, barbiturates
Opiates: heroine, morphine
Stimulants: amphetamines,cocaine,ecstasy
Hallucinogens: LSD, magic mushrooms
Inhalants: glue, solvents
Cannabis (classed alone) - 4What r mechanisms of psychological dependence?All drugs trigger reward & reinforcement mechanisms: ↑DA=>↑reward (cortex)
Opiates, alcohol, cannabis: inhibit GABA inhibition of VTA/DA neurons
Nicotine: stimulates VTA/DA neurons
Cocaine, MDMA: ↑synaptic DA levels - 5What r mechanisms of physical dependence?Only depressant drugs can trigger
adaptive mechanisms:
Normal: excitation=inhibition
Depressants: excitation inhibition (withdrawal symptoms opposite acute effects of drug) - 6What r acute & withdrawal heroin effects?Acute: pain↓, reflexes↓, secretions↓, temperature↓, constipation, cough↓, anxiety↓
Withdrawal: aches+pains, kick the habit, tears, runny nose , fever, diarrhoea, coughing, panicky - 7How can you treat physical dependence?1. In past, aversion (electric shocks)
2. Substitution therapy (methadone-similar to heroine but legal, longer & better, naxolone - antagonist)
3. Residential/priory(psychological support) - 8What r mechanisms, effects & side effects of cannabis?Mechanisms: CB1R & CB2R (slow 2nd messengers, 1 is central) but weak R coupling compared to opiates
Effects: SC (analgesia, muscle relaxation),
cortex-hippocampus (mood, sedation, amnesia), ↑appetite
Side effects: psychosis, amotivation... - 9What r low & high dose effects of stimulants?Low dose: ↑mood, ↑E, insomnia, restlessness (↑motor), hyperactive ideation, ↑talk, mild anorexia, ↑libido
High dose: irritability,hostility, extreme E, total insomnia, motor stereotypies, disjointed ideas, rambling,total anorexia, ↓sexual interest - 10How do stimulants work?Stimulants act on NA, DA, 5HT
Cocaine: blocks reuptake (DA, NA) (similar to NT but blocks transporter) (mainly NA)
MDMA: causes release (even + similar, taken up by transporter) (mainly 5HT)
(Heroin, cannabis=>inhibitory μR&CB1R) - 11What r symptoms&mechanisms cocaine?Symptoms: mood, confidence, alert, dry mouth, palpitations, anxiety&panic, heart failure (bp+HR↑) cerebral hemorrhage
Mechanisms: blocks reuptake=>↑DA+NA
(mainly NA=>cardiac effects) - 12What r mechanisms&effects of amphetamines?Mechanisms: enter terminal through uptake=>release NT (mainly DA, NA, 5HT)
Effects: alert, awake, confident (NA), amphetamine psychosis (DA), motor problems-chewing (DA), fatigue, anorexia - 13What r mechanisms&effects of MDMA-ecstasy?Mechanisms: ↑5HT (mainly 5HT, DA)
Effects: E, calm, T changes,visual changes (5HT), ↑sense of surroundings, empathy,
autoR may be activated (↓release, activity of neurons & synthesis of 5HT):
Short term: 5HT depletion (3/4 days)
Long term: depression, memory loss - 14What r mechanisms&effects of opioids (e.g. heroine, morphine)?Morphine: opium poppy juice
Heroin/diamorphine: enters brain rapidly where converts to morphine
Opioid peptides have 4 opioid Rs
Morphine: μopioidR (opens K IC=>inhibit)
Effects: reward, reduced anxiety (cortex), respiratory depression, nausea, cough, analgesia in brainstem, analgesia in SC, constipation in PNS
Pain blocks reward (patients don1't become dependent)
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- Neuroscience Flashcards on Drugs of abuse, created by Francisco Sacadura on 01/02/2017.
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- Francisco Sacadura
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