Drug abuse Flashcards
What is drug abuse?
Is the recurrent use of illegal drugs, or the misues of prescription or over the counter drugs with negative consequences
Name the different types of drugs that are abused and provide an example for each?
Psychomotor stimulants - Amphetamine/ cocaine
Psychotomimetic agents - Cannabis/ Lysergic acid diethylamide
Opioids - Morphine/ heroin
CNS depressants - Ethanol/ Barbiturates/ Benzodiazepines
What are the reasons to which individuals may abuse drugs and provide examples for each
Mental/ emotional -
interfers with brain function e.g depression, anxiety, difficult concentration, personality and psychotic disorders
Physical -
sleepiness, irrritability, heart failure , stroke
Social -
Withdrawing from family and friends, loss of interest in school and othe activities
What occurs in a normal reward system?
-Sastifying survival and pleasure needs causes the brain’s monitor cells to send chemical signals to the reward center, and this pleasure or reward is recorded in the memory
What occurs in drug/alcohol reward system?
- Drug/alcohol provides artificial feelings of pleasure and the true survival
- Pleasure signals can be completelt ignored
- The subconscious memory records this as a reward
Dopamine is the main NT in the brain? TRUE OR FALSE?
TRUE
What are the different compartments that form the principle dopaminergic tracts?
- Nigrostriatal tract
- Mesolimbic tract
- Mesocortical tract
- Tuberoinfundibular tract
Describe all the 4 compartments of the dopaminergic tract?
- Nigrostriatal tract : Begins in the substantia nigra and ends in the caudate nucleus and putamen of the basal ganglia
- Mesolimbic tract : Originates in the midbrain tegmentum and innervates the nucleus accumbens and adjacent limbic structures
- Mesocortical tract : Originates in the midbrain tegmentum and innervates anterior cortical areas
- Tuberoinfundibular tract : Projects from the arcuate and periventricular nuclei of the hypothalamus to the pituitary
What is the role of dopamine in addiction?
Individuals genes causes low D2 receptors, this leads to increase in pleasure from abused drugs, which leads to drug abuse cycle goes back to low D2 receptors
What factors cause low D2 receptors?
- Abuse, neglect in childhood
What is drug dependence?
A complex disorder in the brain
What occurs to an individual when they have withdrawal syndrome?
- Adaptation in brain reward system manifest as dysphoria and drug craving
- Physical/psychological adevrse effects of cessation of use of the drug
- The abuser will use drug again to relieve or avoid withdrawal symptoms
How I drug addiction (dependence) defined?
A complex disorder (disease) in the brain, it is as state whereby an organism functions normally only in the presence of a drug
What effect does acute or chronic abstinence cause?
Causes withdrawal symptoms
What is drug tolerance?
Decrease in pharmacological effect with repeated use
What are the short and long term causes of drug tolerance?
Short term - Due to depleted levels of NT in vesicles
Long term - Due to the down regulation of the receptors
What is state produced in drug tolerance?
Acute drug state or chronic drug state
Describe the mechanism in drug tolerance?
- Activation of mesolimbic DA pathway
- There are adaptive changes in receptors
- 2nd messengers
What is marijuana (cannabis)?
Dried and crumbled leaves, small stems, flowering tops
In sinsemilla cannabis pollination is prevented which increases the potency of the drug. TRUE OR FALSE?
TRUE
What is hashish prepared from?
Resin
What is the active agent in Cannabis?
THC (Tetrahydocannabinol)
What occurs when marijuana is burned?
-Results in vaporisation of THC absorption into the lungs then into blood plasma
When are these symptoms experienced when an individual is marijuana high? (Euphoria, sedation and pleasant tranquillity)
Begins within a few minutes after inhaling and can last 2-3 hours after initial intoxication
What occurs after peak levels have reached during intoxication?
Concentration falls through metabolism in liver and fat storage
What are the acute psychological effects of cannabis?
- Sensation of relaxation and well being
- Sharpened sensory awareness/sound light appear more intense
- Impairment of short term memory and simple learning
- Impairment of motor co ordination
What are the acute physiological effects of cannabis?
- Increase in HR : Tachycardia - sensation of pounding pulse
- Increase of blood flow to skin: sensation of warmth
- Increase in hunger
Give a few examples of psychomotor stimulants
- Atropine
- Norepinephrine
- Serotonin 5HT
- Dopamine
- Amphetamines
- Cocaine
How do amphetamines work?
- Inhibit monoamine reuptake (NA, Dopamine, 5HT)
- Release stores of NA (nucleus accumbens)
What is cocaine?
Crystalline alkaloid
What are the different ways cocaine can be taken?
- Snorted
- Injected into the vein
- Smoked
What effect does cocaine have on CNS?
Stimulates the CNS
What other symptoms does cocaine cause?
- Appetite suppressant
- Gives rise to a euphoric sense of happiness and increased energy
Cocaine inhibits the reuptake of transporters for monoamines. (DA, NA & 5HT) TRUE OR FALSE?
TRUE
Are opioids receptor agonists or antagonists?
Agonist
What effects do opioids cause?
- Feeling of wellbeing and contentment
- Contributes to analgesic action
Opioids can inhibit GABA. TRUE OR FALSE?
TRUE
What are the desired effects of opioids?
- Euphoria rush
- Decrease in anxiety
- Reduction in pain
What are the undesired long term effects of opioids?
- Hypothermia/ nausea vomiting
- Bone and muscle pain
- Liver and kidney disease
- Risk of stroke
- Lung infection
What are the characteristics of opiates abuse/overdose?
- Respiratory depression (breathing slows down/sometimes to a stop)
- Pinpoint pupils
- Decreased level of consciousness
- Hypotension and bradycardia (heart rate slows down / blue nails, lips)
Is alcohol a CNS depressant or stimulant?
Depressant
Alcohol does not have multiple action sin the CNS. TRUE OR FALSE?
FALSE
What are the multiple actions that alcohol has on the CNS?
- Enhancing the inhibitory actions of GABA at GABAa receptor
- Decreases the excitatory actions of glutamate at NMDA receptors
- Causes the release of dopamine in the NA, increasing serotonin concentration in certain regions
- Stimulating release of endogenous opiates producing euphoria and pain attenuation
What occurs with acute alcohol intake?
- An initial depression of inhibitory neurons producing a sense of relaxation
- Followed by progressive depression of all CNS functions i.e loss of co-ordination
Chronic drinking can lead to the dependence and addiction to alcohol. TRUE OR FALSE?
TRUE
What are the two types of dependences that can occur due to chronic drinking of alcohol?
Psychological
Physiological
What are the withdrawal symptoms of chronic alcohol intake?
- Tremors
- Anxiety
- Sleep problems
- Hallucinations
- seizures
What are the four areas that are focused on during drug addiction treatment?
- Reducing withdrawal discomfort
- Diminishing cravings to the drug
- Blocking rewarding effects of the drug
- Treating comorbidities e.g depression
Treatment must address medical, psychological, social, vocational and legal problems. TRUE OR FALSE?
TRUE
What is an important diagnostic in opioid poisoning?
Pinpoint pupils
