Substance misuse (1) Flashcards
What’s the definition of harmful use?
HARMFUL use → a pattern or use causing clear evidence of HARM.
Pattern has persisted for 1 month or is repeated over 12 month period.
What’s the definition of persistence?
Persistence → _>_3 of:
- COMPULSION to take
- Impaired CONTROL of substance taking behavior
- physiological WITHDRAWAL state
- TOLERANCE
- PREOCCUPATION with drug
- NEGLECT of other activities
- persistence DESPITE HARM
Alcohol (ethanol)
- class
- MoA
Alcohol (ethanol)
Class: CNS depressant
Mechanism of action:
- GABA agonism → suppresses CNS
- Increased dopamine → activates ‘reward’ pathway
SEs of alcohol use
- GIT ulcers
- Pancreatitis
- Gastritis
- Hepatitis
- Cirrhosis
- Dementia
- Peripheral neuropathy
- Cancer (breast, bowel, oesophogeal, liver)
- Depressions, suicide, Korsakoff’s psychosis.
- Long term increased risk of dementia.
- Delirium tremens can occur with withdrawal
- Must taper down intake, dangerous to quit abruptly
Pharmacological interventions for alcohol (ethanol) abuse
- Benzodiazepine → anxiolytic and anticonvulsant properties
- Chlordiazepoxide (“Librium”) → long active benzo
- Thiamine → deficiency common in EtOH. Give to prevent Wernicke’s encephalopathy.
- Disulfiram a.k.a. Antabuse → inhibits acetaldehyde dehydrogenase →causes a buildup of acetaldehyde → ‘hangover-like’ effect if user drinks: flushing, headache, N/V, tachycardia, hypos.
- Naltrexone a.k.a. ReVie → blocks opioid receptor
- Acamprosate a.k.a. Campral → decreases cravings (stabalize chem signaling; poss NMDA recept)
Desired effects ith opioid (e.g. heroin) use
OPIOIDS → HEROIN (Diamorphine) (synthetic)
- Initial ‘rush’ in IV use
- associated with feelings of euphoria, warmth and wellbeing
- Later analgesic and sedative effect
SEs of opioids (e.g. Heroin) use
- Risk of overdose
- Dysphoria
- Cramps
- Vomiting
- Diarrhea
- Sweating
Class and MoA of Heroin
Heroin
Class: opioid
- Opioid derivative → Mu receptor
Other (informal) names for heroin
- Inject
- snort (after heat; “chasing dragon”)
What’s opioid substitution treatment?
Opioid Substitution Treatment (OST) - for Heroin/opioid abuse
- Clearly defined process lasting 28 days – 12 weeks as outpatient
- Must have compliance from patient / not forced
- Slow reduction to attain lower doses
What’s Methadone?
Methadone is used in the treatment of Heroin/opioid abuse
- Mu agonist → binds mu receptor producing a high, but is a known/controlled drug/dose
- Accumulates in tissues and slowly releases into blood stream with tapering off drug
- Following stabilization reduce by 5mg every 1-2 weeks
What’s Buprenorphine?
Buprenorphine → used in Rx of Heroin (opioid) abuse
- FULL antagonist at the opioid kappa (κ) receptor associated with antidepressant effects and ‘clarity of mind
- PARTIAL agonist at Mu and Nociceptin receptors
- Reduce by 2mg every 2 weeks
What’s Lofexidine?
Lofexidine for Heroin/opioid abuse
- a-2 adrenergic (2A) receptor agonist
- Course 7-10 days
- For detox over shorter time with mild/uncertain dependence
What’s Naltrexone?
Naltrexone used in the management of heroin/opioid abuse
- Relapse prevention
- Opioid antagonist → blocks effects
- Bumps any opioids off receptors and into system
- * Torsades des pointes! Don’t give until detoxed!
What’s naloxone?
Naloxone
- antidiote for opioid overdose
- it’s competative opioid antagonist
Pharmacological interventions for Fentanyl abuse
*same as for heroin
