Flashcards in Week 12 Substance Abuse Deck (102)
What are the guidelines for drinking for daily & weekly drinking for Men & Women?
Low risk Males:
daily up to 6, no more than 3 days/week; 28/week
Low risk Females:
Daily up to 4, no more than 3 days/week; 14/week
Daily 7-10 on any day; 29-42/week
Daily 5-6 on any day; 15-28/week
High Risk Males:
Daily 11+ on any day; 43+/week
High Risk Females:
Daily 7+ on any day; 29+/week
Which drugs are Benzodiazepines?
*Diazepam (valium, valpam)
*Clonazepam (klonipin, rivotril)
*Oxazepam (serapax, murelax)
*Temazepam (normison, temaze)
What are Benzodiazepines?
*Agonists of the benzodiazepine site on the GABAA receptor
*Increase ability of GABA to activate GABAA receptor, enhances inhibitory neurotransmission
*“Z drugs” have different chemical structure, but similar pharmacological activity:
How are Benzodiazepines used?
Replaced more dangerous barbiturates for most clinical applications during 1960s-70s
-Anxiolytic: stop panic attacks
-Anticonvulsant: control of seizures
-Occasionally used in anaesthesia
-Reduce alcohol and opioid withdrawal symptoms
*Rapid, high tolerance should limit long-term medical use, but often doesn’t
What are some of the acute effects of Benzodiazepines?
*Relaxation, loss of inhibition, euphoria
*Sedation, lack of muscular coordination
*Enhances effects of alcohol, opiates
*Overdose: respiratory depression, coma, cardiac arrest
What are some of the chronic effects of Benzodiazepines?
*Paradoxical effects, e.g. increased anxiety
-Similar to alcohol withdrawal syndrome
-Extremely dangerous and prolonged:
-Acute symptoms last up to 2 months
-Residual symptoms can last 6-36 months
-Re-emergence of severe withdrawal after single use many months after cessation
What is Nicotine?
Primary psychoactive ingredient in tobacco: accounts for the acute pharmacological effects of tobacco and the subsequent dependence on cigarettes.
•Numerous chemicals in tobacco smoke. Nicotine has some harmful effects, but most harmful effects of tobacco smoking are due to other chemicals.
•Agonist at nicotinic acetylcholine receptors
•Effects in central and peripheral nervous systems, heart, and cardiovascular system
•Brain areas activated by nicotine include:
• Locus coeruleus (behavioural arousal and vigilance)
• Frontal lobes and cingulate gyrus (cognition, working-memory, attention, motivation, mood, and emotion)
What are the behavioural, cognitive, & Psychological effects of Nicotine use?
*Improved working memory
*Improved performance in vigilance and rapid information processing tasks
*Dizziness (in non-tolerant smokers)
Smokers unconsciously self-titrate to optimize nicotine levels and keep them at steady-state.
What are the consequences of tobacco use with regard it's toxicity?
*Smoking is the leading preventable cause of death, illness and disability: causes 4.3 million deaths annually.
*It is the tar in tobacco that leads to much of the long-term toxicity
-Lung cancer, non-cancerous lung diseases, cancers of other body organs, heart and cardiovascular diseases.
-It is estimated that 14 min of life is lost for every cigarette smoked
-One in every six people who try smoking will eventually die of a smoking-related illness.
-Serious health risks associated with passive smoking
-Increased risk of spontaneous abortion, stillbirth, preterm delivery, retarded intrauterine growth and early postpartum death when mothers smoke.
What are the consequences of tobacco use with regard dependence on nicotine?
*Smoking does not appear to lead to nicotine tolerance (except for tolerance to dizziness/nausea/vomiting)
*However, clear physiological and psychological dependence does develop
*Withdrawal is characterized by:
-severe craving for nicotine
-irritability, anxiety, anger, restlessness, impatience
-difficulty in concentrating
-increased appetite, weight gain
What is cannabis?
*There are two species of Cannabis:
*Cannabis is AKA marijuana or hemp
*Numerous preparations (e.g. marijuana “buds”, leaves, hashish, hash oil, etc.)
*smoking, eating, drinking, vapourisation
*Major psychoactive ingredient is Δ9-tetrahydrocannabinol (Δ9-THC)
*Several other cannabinoids modify THC’s effects (e.g. cannabidiol)
*THC content ranges widely
THC is the active ingredient in cannabis. What are the effects of THC?
*Agonist at 2 cannabinoid receptors CB1 & CB2:
-Widely expressed throughout brain
-Often located presynaptically, inhibits transmitter release (both excitatory and inhibitory)
-Appears mainly responsible for cannabis’ psychological effects (e.g. on anxiety, cognition, perception)
-Mainly expressed peripherally (e.g. immune system cells, peripheral nerve cells)
-Effects on immune system function, inflammation, pain perception
-Unclear if significantly contributes to psychological effects
What are the acute effects of Cannabis?
*Dependent relative quantities of different cannabinoids present (potency, species, and strain)
*Smoked or vapourised: 2-6 hours; eaten: 4-24 hours
*Impaired attention & S-T memory, altered sensory awareness, altered motor control and posture
*Hallucinogenic at high doses in some users
*Analgesic, anti-inflammatory, appetite stimulant, anti-emetic (possible grounds for medical application)
*Reduced blood pressure
What are the long-term effects of heavy Cannabis use?
*Dose-related decline in IQ scores; reversible with abstinence
*Impaired attention, verbal memory, working memory, information filtering and processing speed (inconsistent findings)
*Reduced hippocampus and amygdala volume (very long-term, heavy daily use).
*Precipitation of onset, or intensification of, underlying psychotic, mood, or personality disorders
*Increases likelihood of developing psychotic disorders, particularly if used heavily during early adolescence.
*Heavy users more likely to abuse other classes of drugs
What are the effects of Cannabis withdrawal?
Generally mild in all but the most heavy users, suggesting that strong physical dependence does not easily develop. Symptoms usually last 1-2 weeks and include:
-Depressed mood or intensified moods
-Loss of appetite
-Insomnia, vivid dreams
-sweating, fever, chills
Dozens of new chemicals have emerged in recent years. What are the effects of synthetic Cannabinoids?
*Sprayed onto non-psychoactive herbal materials (marketed as, “legal highs”, e.g., “spice”, “kronic”, “k2”, etc.) or sold as pure powder on internet
*Little or no scientific testing in humans
*Anecdotal reports of much more harmful effects than natural cannabis:
-Reports of fatal overdoses, heart attacks
-More severe, prolonged withdrawal symptoms in dependent users
-Full agonist vs. partial agonist
What are opioids?
*Natural: opium, morphine, codeine
*Semi-synthetic: heroin, oxycodone, buprenorphine, desomorphine (“krokodil”) etc.
*Synthetic: methadone, fentanyl, tramadol, pethidine, etc.
*Agonist at opioid receptors (m, d, k)
*Clinical Uses: Pain (analgesia), Anti-tussive (prevents cough), Slows bowel (stops diarrhoea), Anaesthesia, Antidepressant (historically, currently experimental only)
*Side-effects: Pupil constriction, nausea, vomiting, constipation, reduced immunity, depressed respiration, itching
What are some of the recreational effects of Opioid use?
*Sense of comfort, elimination of anxiety and other negative emotions
*“Nod”: dream-like sedation (high doses)
*Stimulation in some tolerant users
What happens during an Opioid overdose?
*Severe respiratory depression
*Leading cause of death among opioid-dependent people
*Usually not opioid alone, but in combination with another depressant drug (e.g. alcohol, benzodiazepines)
*Especially dangerous after reduced tolerance:
-Release from prison
What are some of the chronic effects of Opioid use?
*Impaired immune system function
*Reduced testosterone levels in men:
-Reduced sex drive
-Increased risk of osteoporosis
-Reduced muscle strength
What happens during an Opioid withdrawal?
Chills, sweating, cramps, nausea, watery eyes & nose, yawning, severe anxiety and agitation, insomnia.
Duration depends on drug:
*3-7 days for heroin
*Up to 1 month for methadone
*“Post-acute withdrawal syndrome”: Acute withdrawal sometimes followed by depression, insomnia, anhedonia, cravings, anxiety lasting several months
What are stimulants?
*This category includes drugs such as cocaine and the amphetamines
*Also methylphenidate (“Ritalin”, “Concerta”)
*More recently: cathinones and other synthetic drugs (sometimes marketed as “bath salts” or “synthetic cocaine”)
*Primary mechanism of action in CNS: Increase dopaminergic activity:
-Cocaine: inhibits re-uptake of dopamine
-Amphetamines: increase dopamine release
Tell me about Cocaine
*Used medically as a local anaesthetic
*Used traditionally (chewed coca leaves) by indigenous people of Andes to reduce fatigue and hunger.
*“Crack” is smokable “freebase” form
*Effects last from a few minutes to 1 hour
Tell me about amphetamines?
*Used in the treatment of narcolepsy and ADHD (“dexedrine”, “dexamphetamine”, “adderall”)
*Illicitly marketed as “speed” (rare in Australia), or illicitly diverted pharmaceutical amphetamine (“dexies”)
*Similar medical applications as amphetamine (“desoxyn”)
*Illicitly, can appear as “speed”, “base”, or “ice”
*Effects last up to 12 hours
*More neurotoxic than amphetamine and cocaine
What are the acute effects of stimulants?
*Increased alertness, energy, insomnia
*Euphoria, confidence, grandiosity
*Prolonged use or high doses: anxiety, agitation, paranoia, psychosis
*Increased blood pressure, heart rate
*Overdose can cause stroke or heart attack
What are the chronic effects of stimulants?
*Dental problems from tooth grinding
*Route Of Access dependent:
-“crack lung”, “meth mouth”, nasal damage from snorting cocaine, abscesses from frequently injecting cocaine
*Methamphetamine: neurotoxicity leading to Parkinson’s disease, cognitive deficits
What happens during stimulant withdrawal?
*hypersomnia, lethargy, and fatigue
*apathy, depressed mood,
*irritability, anxiety, agitation
*Lasts several days to several months, depending on duration and amount of use
What is MDMA?
*AKA“Ecstasy” or “molly”
*Occasionally used in psychotherapy in 1970s and 1980s before being banned.
*Recent experimental use as treatment for PTSD
*Closely-related drugs: MDA (metabolite), MDEA
*Releases serotonin and other monoamines (dopamine and noradrenaline), activates 5-HT1 and 5-HT2 receptors
*“empathogen” or “entactogen”; combination of stimulant and psychedelic effects
What can you tell me about the neurotoxicity of MDMA?
*Serotonin neurotoxicity: likely to be exacerbated by hyperthermia (especially use in crowded environments, prolonged dancing):
-Impaired verbal and visual memory
-Impaired decision-making (“executive functioning”)
-Greater impulsivity and lack of self-control
-Depression and anxiety
*Deficits may persist up to a year following frequent, heavy use