Substance use disorder Flashcards
Addiction
General
is a primary, chronic disease of brain reward, motivation, memory and related circuitry. Dysfunction in these circuits leads to characteristic biological, psychological, and social manifestations.
Addiction affects neurotransmission and interactions within reward structures of the brain, including….
The nucleus accumbens (the “reward center”)
The anterior cingulate cortex (ACC)
The basal forebrain
The amygdala
Genetic factors account for about half of the likelihood that an individual will develop addiction
The presence of co-occurring psychiatric disorders in persons who engage in substance use or other addictive behaviors
ADHD, Anxiety Disorders, Depressive Disorders, Personality Disorders, Bipolar Disorders
addiction
patho- Reward
In a “normal brain” dopamine is released from the ACC to the NC when we do things that promote survival (drinking water, eating food, having sex, and sleeping) as a positive reinforcement mechanism.
Various substances, including all of the most commonly abused substances, hijack this system by releasing significantly higher levels of dopamine from the ACC into the NC, and for a greater duration of time. After this occurs, victims are now much more likely to repeat the behavior as nothing else is able to produce that type of euphoria - their reward center has been introduced to a new threshold of pleasure
Addiction
Patho- Memory
Addiction also affects neurotransmission and interactions between….
The cortical and hippocampal circuits and the nucleus accumbens, such that the memory of previous exposures to rewards (such as heroin) leads to a biological and behavioral response to external cues → triggering craving and/or engagement in addictive behaviors.
Addiction
Pathophysiology - The Frontal Lobe & Cortex
Frontal lobe is responsible for:
Storing negative consequences to avoid poor actions in the future
Inhibiting impulsivity and appropriately delay gratification
Patients with addiction have a severely underdeveloped frontal lobe. Meaning high impulsivity and difficulty recognizing consequences of poor choices.
Addiction
Pathophysiology - summary
Inactive front lobe
(decreased impulse control and decreased ability to utilize learned social behavior and logic)
+
Hyperactive reward center
(which now has a new standard for gratification)
=
a patient with very little control over their drug use
Addiction
Genetics
Resiliencies which the individual acquires (through parenting or later life experiences) can affect the extent to which genetic predispositions lead to the behavior and other manifestations of addiction
Patients can be born with underlying biological deficits in the function of reward circuits resulting in a exaggerated reward response within the NA
Substance abuse Disorder DSM Criteria
A problematic pattern of “substance” use leading to clinically significant impairment or distress, as manifested by at least 2 of the following, occuring within a 12 month period:
- Substance is taken in larger amounts or over a longer period than was intended
- There is a persistent desire or unsuccessful efforts to cut down or control substance use.
- A great deal of time is spent in activities necessary to obtain, use, or recover from it’s effects
- Craving, or a strong desire or urge to use the substance
- Recurrent substance use resulting in a failure to fulfill major role obligations at work, school, or home
- Continued substance use despite having persistent or recurrent social or interpersonal problems caused or exacerbated by the effects of the substance
- Important social/work/ rec activities are given up or reduced because of use
- Recurrent use in situations in which it is physically hazardous
- Use is continued despite knowledge of having a persistent or recurrent physical or psych problem that is likely to have been caused or worsened by substance
- Tolerance
- Withdrawal
SUD
Specifiers and severity
Specifiers
In early remission: no criteria met for at least 3 months, but less than 12 (except cravings)
In sustained remission: no criteria met for 12 months (except cravings)
In controlled environment
Severity
Mild: 2-3 symptom criteria met
Moderate: 4-5
Severe: 6+
Alcohol Use Disorder
RF
Family history of alcohol use disorder and other substance use disorders
Availability of alcohol
Heavy alcohol use
Binge drinking
Permissive societal attitudes towards alcohol use
History of childhood abuse
History of conduct or mood disorder in childhood
Having mental health conditions such as depression or post-traumatic stress disorder
Impulsivity
Alcohol Use Disorder
At-Risk Drinking criteria
At-Risk Drinking:
Men: more than 4 drinks/day, or more than 14 drinks/week
Women: more than 3 drinks/day, or more than 7 drinks/week
Men and Women over age 65: More than 3 drinks/day, or more than 7 drinks/week
alcohol use disorder
Binge Drinking criteria
Men: 5 or more drinks in a 2- to 3-hour period
Women: 4 or more drinks in a 2- to 3-hour period
Alcohol use disorder
SCREENING
AUDIT - 10 question - best screening tool
CAGE - 4 questions (cut down, annoyed, guilty, eye-opener)
MAST - 25 question
AUD
comorbidities
Repeated use in high amounts can impair nearly every organ system
Gastritis
Stomach/duodenal ulcers
Liver cirrhosis
Pancreatitis
Esophageal and stomach cancer
Hypertension
Cardiomyopathies, hypertriglyceridemia, elevated LDL
Myopathies
Severe memory impairment
Degenerative changes in the cerebellum
Thiamine deficiency → Wernicke-Korsakoff Syndrome
AUD
Lab markers
BAC, or blood alcohol concentration: (>200mg/dL in any non-tolerant pt should demonstrate severe intox)
GGT (gamma-glutamyltransferase) - high-normal - About 70% of patients with elevated GGT are persistently heavy drinkers (8+ per day)
CDT (carbohydrate-deficient transferrin) - levels of 20 units or higher can be useful in identifying individuals who drink/abuse alcohol regularly
MCV - high-normal, but not a good predictor of abstinence due to long lifespan of RBC’s
LFT’s - AST:ALT ratio > 2:1 is indicative of heavy alcohol use
Alcohol Intoxication
general
Slurred speech, Incoordination, Unsteady gait, Nystagmus, Impairment in attention/memory, Stupor/coma
BAC over 300-400 mg/dL can cause inhibition of respiration → death
In general, the body is able to metabolize about 1 drink per hour and BAC should fall about 15-20mg/dL per hour
THERE IS A SIGNIFICANTLY INCREASED RATE OF SUICIDE DURING ALCOHOL INTOXICATION
AUD -tx
Acamprosate (Campral)
666mg 3x daily (initial and therapeutic dose) - start lower if renal impairment is present
No labs required, but should be avoided in patients with severe renal impairment
Glutamate neurotransmission modulation at metabotropic-5 glutamate receptor sites
MC side effects: diarrhea, nervousness, and fatigue
Can take with naltrexone and disulfiram and in pts who continue to drink
Contraindication: severe renal impairment (CrCl 30 or less)
AUD - tx
Naltrexone (mu opioid receptor blocker)
Partial antagonist
50mg PO once daily or 380mg IM q4wks
Requires monitoring of LFTs q 6months
Mice that lack the mu-opioid receptor do not self-administer alcohol
Naltrexone also modifies the HPA axis to suppress ethanol consumption
Reduces heavy drinking by only about 25%
Contraindication: acute hepatitis and liver failure
AUD
Disulfiram (Antabuse)
125-500mg once daily
discourages drinking by causing an unpleasant physiologic reaction when alcohol is consumed
Inhibits aldehyde dehydrogenase and prevents the metabolism of alcohol’s primary metabolite, acetaldehyde
Results in sweating, headache, dyspnea, lowered blood pressure, flushing, sympathetic overactivity, palpitations, nausea, and vomiting if alcohol were to be consumed
initially dosed at 500 mg/day for 1-2 weeks, followed by an avg maintenance dose of 250 mg/day with a range from 125-500 mg based on the severity of adverse effect
Side effects; rash, drowsiness, HA, metallic taste, hepatitis
AUD
Disulfirm- contraindications
Contraindications: severe myocardial disease and/or coronary occlusion, psychosis, or known hypersensitivity to the medication or other thiuram derivatives. Also avoid in pregnancy and during breastfeeding
AUD
CIWA
Withdrawal assessment
Opioid abuse
Intoxication Sx
Euphoria
Sedation
Slurred speech
Constipation
Analgesia
Decreased respirations
Attentional deficits
Pinpoint pupils
