SEARCH RESULTS FOR: Opioid-Use-Disorder

Opioid Use Disorder

Opioid Use Disorder: Clinical Findings and Complications Opioids act on mu, kappa & delta opioid receptors Widespread accumulation of opioids Excessive glutamate exposure Overstimulation of membrane receptors (i.e., Neuronal excitotoxicity) Neuronal injury or death Myoclonus (involuntary muscle twitches/jerks) In brain & brain stem Parasympathetic stimulation of oculomotor nerve (cranial nerve 3) Suppression of reticular activating system neurons Cessation of respiration Contraction of pupillary sphincter ↓ Excitatory input to the cortices ↓ Arousal Lack of oxygen in the brain & other organs Miosis (pupil constriction) ↓ Level of Consciousness Death ↓ GABA release in ventral tegmental area Activation of mesolimbic dopaminergic pathway Release of dopamine in nucleus accumbens ↓ Traumatic memories ↓ Acetylcholine release in GI tract ↓ Peristalsis in GI tract ↓ GI transit & motility ↑ Time for colonic absorption of water Constipation Activation of mu & delta receptors in medulla’s chemoreceptor trigger zone Nausea Activation of mu receptors in the pons & medulla ↓ Neural drive for breathing ↓ Respiration Euphoria Analgesia Craving, strong desire to use More frequent opioid use Authors: Keira Britto Kayla Marritt Meera Grover* Reviewers: Erik Fraunberger Sara Cho, Luiza Radu Spencer Krahn * * MD at time of publication Opioid Use Disorder: Pattern of opioid use leading to clinically significant impairment or distress Performing any given behaviour while intoxicated cAMP Mechanism upregulation unknown Mu opioid receptor desensitization Physical dependence reinforces opioid use Opioid withdrawal with cessation** Unable to ↓ or stop opioid usage With chronic use, ↓ response to opioids Behaviour tolerance ↑ Opioid required to achieve euphoria & analgesia (i.e., tolerance) ↑ Quantity & prolonged opioid consumption ↑ Time spent obtaining, using, & recovering from opioids Recurrent opioid use in physically hazardous situations despite physical, psychological, social & interpersonal consequences ↓ Participation in occupational social & recreational activities ↓ Fulfillment of work, school & personal obligations **See relevant Calgary Guide slide Legend: Pathophysiology Mechanism Sign/Symptom/Lab Finding Complications Published Jan 28, 2025 on www.thecalgaryguide.com