Introduction to Opioids, OUD, and Withdrawal Flashcards
Opioids may be used to…
Reduce pain
Manage opioid dependence
Produce temporary euphoria/relaxation
The 3 main opioid receptor subtypes include…
Mu, delta, and kappa
Mu receptors are responsible for…
Most of the opioid analgesic effect
Also causes respiratory depression, reduced GI motility, euphoria, sedation, and physical dependence
Delta receptors are responsible for…
Analgesia, euphoria, physical dependence
Kappa receptors are responsible for…
Analgesia, sedation
Questionable effect on mood
Does NOT contribute to physical dependence
Opioid use disorder is…
A long-lasting chronic brain disease, involving recurrent use of opioids causing significant clinical + functional impairment due to cumulative impact of opioids on the brain
Is often relapsing and requires long-term chronic disease management
OUD without treatment or engagement in recovery activities…
Is an addiction, progressive, and can result in disability or premature death
DSM-5 discusses components of OUD such as…
Problems with USE - using large amounts, more time spent with use, repeated attempts to control use
Problems with LIFESTYLE - physical/psych/social/interpersonal problems related to use, activities given up, neglected major roles, hazardous use
Problems with PHYSIOLOGY - craving, tolerance, withdrawal
Severity needs to be individualized
Manifestations of OUD can involve…
Misuse of prescribed opioid medications
Use of diverted opioid medications
Use of illicitly obtained opioids
It is important to note that OUD does NOT end when…
The drug is removed from the body, or when acute post-drug taking illness dissipates
OUD is similar to other chronic disease such as T2DM and HTN in that…
It cannot be cured, but can be treated and managed
The leading cause of death among people using opioids is…
Opioid toxicity and trauma
OUD is associated with increased morbidity + mortality
The cycle of OUD involves the 3 stages of addiction, which include…
Binge/intoxication - individual consumes intoxicating substance, experiencing rewarding/pleasurable effects
Withdrawal/negative affect - individual experiences negative emotional state in absence of substance
Preoccupation/anticipation - individual seeks substance again after period of abstinence
3 stages are linked to + feed on each other, involving different brain regions, circuits, NT’s - result in specific kinds of changes in the brain
The intensity and frequency of the OUD cycle can vary…
Frequency - course of weeks/months, or several times in a day
Intensity - variation in how people progress, and intensity
The addiction cycle tends to intensify over time, leading to…
Greater physical and psychological harm
When an opioid attaches to the Mu receptor, it triggers a structure in the brain called…
Related to euphoric feeling and opioid tolerance
The mesolimbic (midbrain) reward system in the ventral tegmental area (VTA)
The VTA system is responsible for the release of ____ in the ____, resulting in pleasure.
Release of dopamine in the nucleus accumbens (NAc)
Feedback to the prefrontal cortex to the VTA regulates…
The drive to obtain pleasure (risk vs. reward)
Overtime, with the repeated opioid use, the feedback pathway between the prefrontal cortex to VTA becomes dysregulated, which…
Impairs decision making
Development of opioid tolerance results from…
The opioid receptors in the VTA become less sensitive to opioid stimulation - dopamine production is reduced and the experience of pleasure/opioid is diminished
Higher and higher doses are required to achieve the same pleasure reward
Neurons in the locus coeruleus (LC) function by…
Producing NE and distribute it to other parts of the brain where it stimulates wakefulness, breathing blood pressure, alertness (fight/flight)
When opioids bind to Mu receptors in the LC, they…
Suppress release of NE, causing drowsiness, hypotension, and slowed respiration (resulting in opioid intoxication)
Which can result in death; hence why harm reduction is extremely critical
The MOA of naloxone is to…
Bind the same sites as the opioids in the brain more tightly - displaces opioid and acts as an antagonist at the receptor
Naloxone helps to ____ within ____, when…
Restore breathing within 2-5 minutes, when it has been dangerously slowed/stopped due to opioid usage
