Addiction and drugs of abuse Flashcards
What is the psychoactive component in cannabis?
THC
Binds to CB1 receptors
(Leads to an indirect dopamine release)
How long does cannabis remain in the body?
Lipid soluble so remains in system for longer
Days in infrequent use / weeks in chronic use
What are the psychological effects of cannabis?
Relaxation
Euphoria
Altered perceptions
Irritability
Paranoia
What are the physical effects of cannabis?
Dry mouth
Dry eyes
Tachycardia
Hunger
What are the chronic / adverse effects of cannabis?
Low motivation
Depression
Anxiety (major factor in perpetuation of cycle of use)
Psychosis
Associated tobacco risks
What effects does MDMA have on the brain?
Blocks SEROTONIN reuptake so increases quantity of free serotonin at synapse
Increases dopamine (reward, pleasure) and noradrenaline (stimulant)
What are the psychological effects of MDMA?
Euphoria
Increased EMPATHY towards others
Increased energy
Altered perceptions eg SYNAESTHESIA
What are the physical effects of MDMA?
Hyperthermia
Dry mouth
MYDRIASIS
Hypertension
Tachycardia
BRUXISM (clenched / grinding jaw)
What are the chronic / adverse / come down effects of MDMA?
COME DOWN: anxiety, low mood, low energy
ADVERSE: low mood, anxiety, overdose, HYPONATRAEMIA secondary to water intoxication –> seizure –> DEATH
What effect do amphetamines have on the brain?
DISRUPTS STORAGE OF NEUROTRANSMITTERS such as dopamine, serotonin and noradrenaline in synaptic vesicles
Leads to increased amounts due to transporters running in reverse –> STIMULANT effect
What are the physical effects of amphetamines?
TACHYCARDIA
Hypertension
Increased resp rate
DECREASED HUNGER + NEED FOR SLEEP
What are the chronic / come down / withdrawal effects of amphetamines?
COME DOWN: low mood, lethargy
CHRONIC: psychosis, depression, anxiety, dependence
WITHDRAWAL: cravings, low mood, increased sleep, anhedonia
What effects does LSD have on the brain?
Binds to 5-HT receptors causing serotonin release
ALTERS SHAPE of receptor to form a stronger bind –> LONGER half-life and effect
Increased levels of dopamine and glutamte
What are the psychological effects of LSD?
Can vary
Altered perceptual states (synaesthesia, dissolution)
Visual and auditory hallucinations
What are the physical effects of LSD?
Mild tachycardia
Mild hyperthermia
Mydriasis
What are the come down / adverse effects of LSD?
COME DOWN: anxiety, reduced concentration, reduced appetite
ADVERSE: bad trip, risk of PSYCHOSIS in CHRONIC use but does not induce dependence
HPPD = Hallucinogen Persisting Perception Disorder - continuing to experience perceptual distortions months / years after stopping drug
What effect does heroin have on the brain?
A PRO-DRUG - crosses blood-brain barrier and is converted to MORPHINE
Binds to MU-OPIOID receptors –> euphoria and analgesia
Inhibits GABA causing increased DOPAMINE
What are the psychological effects of heroin?
Euphoria
Relaxation
Sense of COMFORT
Anxiolytic
What are the physical effects of heroin?
REDUCED RESP RATE
Bradycardia
CNS depression
CONSTRICTED PUPILS
What are the come down / adverse effects of heroin?
Tolerance soon develops –> dependence
DEATH due to RESPIRATORY DEPRESSION
Significant withdrawal features
What are the effects of cocaine / crack on the brain?
Blocks MONOAMINE reuptake transporters
Leading to increased dopamine, noradrenaline and serotonin
Crack = short half-life (minutes), Cocaine = longer, less sharp high
What are the psychological effects of cocaine / crack?
Elation
Increased ENERGY
CONFIDENCE
What are the physical effects of cocaine / crack?
Dry mouth
MYRDIASIS
Vasoconstriction
TACHYCARDIA
Decreased appetite
What are the come down / adverse effects of cocaine / crack?
COME DOWN: low mood, irritability, tremors, difficulty concentrating
ADVERSE: stroke, CARDIAC TOXICITY, ENT complications
What are the biological treatment approaches for addiction and drugs of abuse?
ANTIDOTES –> naloxone (opioids), flumazenil (Benzos)
DETOXIFICATION –> methadone, diazepam
SUBSTATION –> methadone, buprenorphine
DETERRENCE –> disulfiram (alcohol)
ANTI-CRAVING –> acamprosate (maintenance of abstinence), naltrexone (for cutting down)
What is the recommended psychological treatment for substance abuse?
Motivational interviewing - works to increase motivation to stop
Brief interventions
CBT
Contingency management
Self help
What are the opiate replacement therapy options?
Both have long half-life and prevent withdrawals without giving an opiate high
METHADONE
-Liquid (luminous green, tablet / injection
-10-30mg/daily (starting dose)
-Maintenance up to 100mg daily under supervision
BUPRENORPHINE
-Tablet, sublingual or depot
-4mg/day (starting dose)
-Maintenance up to 8-16mg or 32mg under supervision
-Blocking action means illicit use does not produce a high
What is important to remember when giving buprenorphine to an opiate user?
Has partial agonist and antagonist properties so can precipitate a WITHDRAWAL in those using high dose opiates
What are the key symptoms of opiate withdrawal vs overdose?
OVERDOSE:
-RESP DEPRESSION
-Bradycardia
-Reduced GCS
-Pinpoint pupils
WITHDRAWAL:
-Muscle aches, lacrimation, agitation
-Excessive yawning, rhinorrhoea
- Sweating, tachycardia, HTN, sleep disturbance (autonomic hyperactivity, N+V+D, dysphoria, craving
What is the treatment for overdoses?
NALOXONE
Competitive opiate antagonist (V SHORT HALF-LIFE so beware risk of further overdose in cases of long-acting high dose opiates)
IM and nasal spray
