Substance Disorders Flashcards
What defines a substance abuse problem?
it is a pattern of use that leads to impairment or distress for at least 12 months with one or more of the following:
- failure to fulfill obligations
- use in dangerous situations
- use-related legal problems
- continued use despite social or interpersonal problems
What defines a substance dependence?
it is a pattern of use characterized by at least three of the following within a 12-month period:
- tolerance
- withdrawal
- using more than originally intended
- persistent desire or unsuccessful efforts to reduce use
- significant time spent using
- diminished social, occupational, or recreational engagement
- continued use despite consequent physical or psychological problems
Which opioids will not appear on a general UDS?
methadone and oxycodone will typically come up negative and a separate panel must be ordered
How does alcohol work in the brain?
by activating GABA and serotonin receptors in the CNS while inhibiting glutamate receptors
How is alcohol metabolized?
- from alcohol to acetaldehyde by alcohol dehydrogenase
- from acetaldehyde to acetic acid by aldehyde dehydrogenase
Describe the presentation and treatment of alcohol withdrawal.
- the classic progression is from autonomic hyperactivity and psychomotor agitation, to alcoholic hallucinosis, to seizures, and then to delirium tremens
- benzodiazepines are the mainstay of therapy and should be supplemented with antipsychotics for severe agitation
- be sure to replace thiamine, folic acid, and magnesium (deficiency predisposes to seizures)
- do not continue long-term anticonvulsants after alcohol withdrawal seizures
What is the CAGE questionnaire?
it is a tool used to screen for alcohol abuse using four questions:
- have you ever considered cutting down?
- have you ever been annoyed by criticism of your drinking?
- have you ever felt guilty about drinking?
- have you ever taken an “eye opener”?
a yes to two or more is considered a positive screening
What is considered at-risk or heavy drinking in men and women?
- for men, more than 4 per day or 14 per week is considered high risk
- for women, more than 3 per day or 7 per week is considered high risk
What are the four most common treatments for alcohol dependence and how does each work?
- disulfiram is an aldehyde dehydrogenase inhibitor
- naltrexone is an opioid receptor blocker that reduces cravings and reduces the high associated with alcohol if they do drink
- acomprosate is similar to GABA and inhibits glutamatergic systems to prevent relapse
- topiramate reduces cravings
Which medication should be used to treat alcohol dependence in someone with liver disease?
acomprosate because it is processed by the kidneys
What mistake can precipitate Wernicke-Korsakoff syndrome?
you must always give thiamine before glucose if you don’t, you may precipitate one of these
Describe Wernicke encephalopathy and Korsakoff syndrome.
- WE: ataxia, confusion, and ocular abnormalities
- KS: amnesia and confabulation
What is the mechanism of action of cocaine and of amphetamines?
- cocaine blocks the reuptake of dopamine
- classic amphetamines block the reuptake and induce the release of dopamine and norepinephrine
- designer amphetamines induce the release of dopamine, norepinephrine, and serotonin
What is the potentially deadly complication of cocaine use?
vasospasm-induced MI or stroke
How is cocaine intoxication managed?
- reassurance and benzodiazepines for moderate symptoms
- haloperidol and other antipsychotics for severe agitation or psychosis
- must monitor temperature and treat fevers aggressively with cooling measures
Describe amphetamine overdose.
typically in the form of hyperthermia leading to dehydration and rhabdomyolysis with subsequent renal failure
How is amphetamine intoxication managed?
with rehydration, correction of electrolyte imbalances, and management of hyperthermia
What is the mechanism of action of PCP and how does intoxication present?
> it is an NMDA receptor antagonist and activates dopaminergic symptoms > symptoms are described by RED DANES - rage - erythema - dilated pupils - delusions - amnesia - nystagmus - excitation - skin dryness
What is rotatory nystagmus?
a finding pathognomonic for PCP intoxication
How is PCP intoxication treated?
- use benzodiazepines to treat moderate agitation, anxiety, muscle spasms, and seizures
- use haloperidol and other antipsychotics for severe agitation and psychosis
How do benzodiazepines and barbiturates function?
benzodiazepines increase the frequency of chloride channel opening while barbiturates increase the duration of opening and at high doses act as direct GABA agonists
How are barbiturate and benzodiazepine overdoses treated?
- barbiturate overdose is treated with sodium bicarb to alkalinize the urine and promote renal excretion
- benzodiazepine overdose is treated with flumazenil
What is the difference between naloxone and naltrexone?
- naloxone is a short-acting competitive antagonist that is useful in the treatment of opioid overdose
- naltrexone is a longer-acting blocker of opioid receptors helpful in maintenance therapy
Describe the presentation of opioid intoxication and withdrawal.
- for intoxication everything constricts: drowsy, constipation, slurred speech, constricted pupils, respiratory depression, seizures
- overdose has a classic triad of respiratory depression, altered mental status, and miosis
- for withdrawal everything dilates: lacrimation, rhinorrhea, yawning, insomnia, sweating, dilated pupils, diarrhea
What is the classic triad of respiratory depression, altered mental status, and miosis?
the presentation for opioid overdose
How is opioid withdrawal treated?
withdrawal is treated with clonidine (for autonomic symptoms), NSAIDs (for pain), and dicyclomine (for abdominal cramps)
What pharmacologic options are available for the treatment of opioid dependence?
- methadone is a long-acting full agonist
- buprenorphine is partial agonist that comes combined with naloxone to prevent diversion (known as suboxone)
- naltrexone is a competitive antagonist that prevents the high associated with use if a relapse occurs
Hallucinogenics are thought to act in what manner?
via serotonin systems
How is hallucinogenic intoxication identified and treated?
- identified based on the symptoms of perceptual changes, labile affect, and dilated pupils
- treat primarily with monitoring but can use benzodiazepines or antipsychotics for severe agitation or psychosis
What is the mechanism of action for marijuana?
it acts on presynaptic cannabinoid receptors to inhibit adenylate cyclase
What is the mechanism of action for caffeine?
it acts as an adenosine antagonist causing an increase in cAMP and a stimulant effect via dopaminergic systems
What are four options for the treatment of nicotine dependence?
- behavioral counseling should be part of all interventions
- nicotine replacement therapy
- bupropion
- varenicline is a nAChR partial agonist and is very effective
