Drug Dependence Flashcards
Define Addiction
Chronic disease characterised by drug seeking and use that is compulsive, or difficult to control, despite harmful consequences
Define Drug Abuse
Pattern of drug use in which the users consume the substance in amounts Use methods which are directly/indirectly harmful to themselves or others
Define drug dependence
Adaptive state that develops after repeated drug use and which results in withdrawal symptoms upon cessation of drug use
Define Drug Tolerance
The diminishing effect of a drug which results after repeated administration at a set dose
Define Psychological dependence
Dependence that involves emotional-motivational withdrawal symptoms (e.g. dysphoria, depression, anhedonia, restlessness)
Define physical dependence
Dependence that involves significant physical-somatic withdrawal symptoms (e.g. fatigue, nausea, seizures, pain, delirium tremens)
How many admission to hospital with a primary diagnosis of a drug-related mental health and behavioural disorder?
6,549
What are class A drugs?
Heroin Methadone Cocaine Crack cocaine Ecstasy LSD Magic mushroom
What are class B drugs?
Amphetamines Barbiturates Ketamine Methylphenidate Codeine Cannabis
What are class C drugs?
Anabolic steroid Benzodiazepine Gamma hydroxybutyrate Gamma butyrolactone Khat
Which drug is deemed most dangerous?
Class A
Which drug is thought to have least capacity for harm?
Class C
Opiates
Agonists at mu opioid receptors
Cocaine
DA,NAd and 5-HT uptake systems
Amphetamine
Monoaminergic transmission: uptake system; agonist of tract amine-associated receptor 1 (TAAR1)
Ethanol
GABA A and NMDA receptors
Nicotine
Nicotinic ACH receptors - agonist
Cannabinoids
CB1 receptors - agonist
Phencyclidine, ketamine
NMDA glutamate receptors - antagonist
Hallucinogens
5-HT2A receptors
Barbiturates and benzodiazepine
GABA A receptors
Solvents
NMDA receptors, nicotinic ACH receptors
Benzodiazepine
Drugs that can be abused but have therapeutic value as hypnotics and anxiolytics
What are the endogenous opioid peptide systems?
Proopiomelanocortin-derived Proenkephalin -derived Prodynorphin derived
What are the Opioid receptors?
Mu (m1,m2,3) Delta Kappa Nociceptin/ orphanin receptors
What are factors determining the development of addiction?
Environment Drug-induced effects Genes
What is essential in reward and the development of drug-dependence?
Dopaminergic projection from ventral tegmental area to the nucleus accumbens
What are the stages of addiction cycle?
Binge/ intoxication Withdrawal/negative effect Preoccupation/Anticipation
What are the brain areas involved in the development of drug dependence?
Ventral tegmental area Nucleus accumbens Amygdala Insula Prefrontal cortex Hippocampus
Which compound is used to treat ADHD?
Metyhlphethamine
What is dopamine Involved in?
Important for first sensation involved in pleasure and reward
What are many withdrawal symptoms categorised by?
High levels of anxiety
What is a common feature of anxiety disorder?
Hyperactivity of the limbic structures
What are the fear/panic symptoms?
Heart rate/blood pressure Bradycardia, ulcers Panting/ respiratory distress Arousal/vigilance/ attention Increased startled response Freezing/ social interaction Corticosteroid release
When an individual takes crack cocaine, what happens in the prefrontal cortex?
The metabolism in prefrontal cortex is changed
What are altered in addicts?
Prefrontal circuits
What are the processes associated with prefrontal cortex and which are impaired in addicts ?
Self control Emotional regulation Motivation Attention and flexibility Working memory Decision making Awareness and insight Learning and memory Salience attribution
What are the core components of addiction?
Intoxication Bingeing Withdrawal Craving
What is intoxication?
Impaired self-awareness
What is Bingeing?
Loss of control
What is Withdrawal?
Amotivation and anhedonia
What is craving?
Drug expectation and attention bias
What are the characteristics of physical dependence?
Physical symptoms of illness Only seen with some abused drug Relatively shorted lived approx 2 weeks Associated with clear cut abstinence syndrome - symptoms of illness occurring on Withdrawal
What are the characteristics of psychological dependence ?
Compulsion, need or craving to take the drug Produced by all drugs of dependence Long lasting Produced by some drugs (cocaine, amphetamine, nicotine, caffeine)
What are examples of withdrawal symptoms of opiates?
Diarrhoea Nausea/ vomiting Abdominal cramps Sweating/ shivering Hypertension Seizures Anxiety/ agitation
What are some withdrawal symptoms of Alcohol?
Seizures Sweating Tremors Delirium tremens (delirium/ vivid hallucination) Anxiety/agitation
What are examples of treatment of withdrawal symptoms?
Clonidine Buprenorphine Carbamazepine
What is clonidine?
Alpha 2 receptor adrenoceptor agonist Management of Withdrawal symptoms in opiate addiction
What is Buprenorphine?
Partial opiate mu receptor agonist Kappa opiated receptor antagonist Management of withdrawal symptoms in opiate addiction
What is carbamazepine ?
Anticonvulsant Drug Sodium channel blocker Reduces seizures associated with alcohol withdrawal
What are sensitive genes ?
Go up and down Indication of stimulation
What is spines?
Where information arrived on dendritic spine important for information processing
What does exposure to drug change?
Architecture of Cell
How are abnormalities in brain caused?
Long term exposure to cocaine/morphine
What does drug dependence induce
Long lasting changes in gene expression Metabolic changes Changes in neurotransmission Global change in brain activity Structural changes
What can Alcohol modulate in the brain?
Both excitatory and inhibitory transmission
What happens when you apply ethanol and NMDA?
Decrease excitatory of glutamate receptors
Apply ethanol and GABA
Enhance function of chloride channel
How can transmission in brain be altered by both excitatory and inhibitory neutrotransmission?
Dose dependent manner and pattern manner
Why is the first phase of alcohol an CNS depressant,?
Enhances gabaminertic transmission
What happens to an Individual that keeps using alcohol?
Adaptation in synapse both glutaminergic and gabaminergic
What is alcohol abuse?
Social drug
What is acute alcohol intoxication?
Euphoria developed followed by depressed mood, slurring of speech, ataxia, general incoordination , pupillary dilation
What does acute alcohol ingestion lead to?
Depressed excitatory transmission Potentiated inhibitory transmission.
What happens to brain of chronic alcoholics?
Brain shrinks - loss of grey matter 12%
What are the treatment for alcohol addiction?
Naltrexone Acamprosate Disulfiram
Naltrexone
Antagonist at mu opioid receptors Rewarding effects of alcohol Reduce relapse
Acamprosate
Modulator of glutamtergic transmission Partial co-agonist at NMDA glutamate receptors Reduces insomnia, anxiety, restlessness and dysphoria
Disulfiram
Interferes with alcohol metabolism Acetylaldehyde cannot be transformed into Acetate - build up in body Flushing, nausea, confusion and irregular heartbeat
What is ecstasy?
Amphetamine
What are the multiple targets for MDMA?
5-HT uptake system Dopamine uptake system 5-HT2 receptors H2 histamine receptors Alpha 2 adrenergic receptors
What does long term recreational use of ecstasy affect?
Cognitive processes - metabolic changes in the brain
What are the acute MDMA toxicity?
Body temperature elevation Disseminated inteavascular coagulation Rhabdomolysis (blocked by danteolene) Increased renal reabsorption of water Hypontraemia and cerebral oedema I
What does prolonged exposure to MDMA lead to?
Loss of serotonin fibres
What receptors does Cannabis have?
CD1 and CD2 —> G protein coupled receptors
What does THC cannabinoids bind to?
CB1 and CB2 receptors
Where is CB1 receptor concentrated in?
Central nervous system
Where are CB2 receptors located?
Peripheral organs and are associated with immune system
Where are CB1 distributed?
Neocortex, hippocampus, basal ganglia, brainstem
What is cannabinoids intoxication symptoms?
Hypothermia, rigid immobility, decreased motor activity
What is the brain rich in?
Cannabinoids
If cannabinoids knocked out?
Lose all affects of cannabis
What does long term use of cannabis increase the risk of?
Schizophrenia and major depression
What is inhaled cannabis?
Marijuana
Why do people use cocaine?
Euphoria Inflated sense of self and increased self-importance Sense of escaping reality Intense burst of energy
What are the effects of cocaine?
Vasoconstriction, pupillary dilatation, hyperthermia, Increased heart rate, increased blood pressure, tremors, restlessness, anxiety, paranoia, vertigo
What are the modes of use of cocaine?
Inhalation, orally, intranasally, intravenously
What are the long term effects of cocaine/ crack addiction?
Cardiovascular issues: heart attack and stroke Marked cognitive decline Persistent psychotic symptoms Major depression and anxiety
What are general principles of treatment of drug addiction?
Detoxification, counselling, medication, treatment for co-occurring mental health issue, long term follow up to prevent relapse
What are treatment of nicotine addiction?
Nicotine replacement therapy: patches, spray, gum and lozenges
What are medication of treatment of nicotine addiction
Bupropion: antidepressant drug; inhibitor of dopamine reuptake) Varenicline
What are the components of comprehensive drug addiction treatment?
Vocational services, mental health services, medical services, educational services, HIV/AIDS services/ legal services, family services
