Substance related disorders Wilkes N552| 62 questions fully solved.

Reward pathway Genetic, environmental, cultural factors interact Primary NT is dopamine Key areas: dopamine mesocorticolimbic system, ventral tegmental area (VTA), nucleus accumbens (NA), the amygdala, olfactory tubercle. , Cocaine and stimulants, such as amphetamines activate the reward system by blocking dopamine reuptake transporter. Opioids activate the same circuitry as the stimulants (initially they activate opioid receptors in the VTA, which ultimately results in an increase in dopamine release in the NA) Ethanol produces its effects by multiple pathways (antagonism of modulation of GABA receptors, activate dopamine indirectly by facilitating activity of GABA neurons in the par reticulata, ultimately disinhibiting the VTA dopamine neurons resulting in increase dopamine in the NA. Nicotine acts on the opioid pathway Marijuana (active component tetrahydrocannabinol, THC) binds to cannabinoid-1 (CB) receptors resulting in activation of dopamine neurons in the mesocorticolimbic system. THC also increases the release dopamine into the shell of the NA. PATHOPHYSIOLOGY Neuronal Adaptation Chronic use of abused substances resulting in both addiction and withdrawal may be related to neuroadaptive effects occurring within the brain. Sensitization Counter adaptation GOALS OF THERAPY o Alleviate the effects of drug intoxication o Attenuate the adverse effects of withdrawal o Decrease craving for, and relapse to, abused substances CLINICAL PRESENTATION AND DIAGNOSIS o Chronic pattern of use of abused substances meet DSM-5 criteria o Pattern of substance abuse that has resulted in undesirable social, occupational, and legal consequences Behavioral Effects Ethanol Labile mood, aggressive or sexual behavior, giddiness or verbally loud, impaired judgment, somnolence and coma. Physiologic Effects Ethanol Variable with blood levels from decreased reaction time, muscle incoordination, ataxia, dysarthria, to respiratory failure coma. Behavioral Effects Cocaine/ stimulants Elated mood, depression, hyper vigliance, anxiety. Impaired judgment, violence, paranoia, psychosis, delusions, increased motor activity. Physiologic Effects Cocaine/ stimulants Neuro: dilated pupils, HA, tremor, hyper-reflexia, twitching, seizures, or coma CV: Increased HR/BP, arrythmias, MI GI: N/B Renal: incontinence/ARF NM: rhabdomyolysis Behavioral Effects Opioids Euphoria, sedation, slurred speech, impaired attention, memory, and psychomotor retardation Physiologic Effects Opioids Nausea and vomiting, respiratory depression, constipation, itching, mioisis. Behavioral Effects Physiologic Cannabis Euphoria, increased appetite, paranoia, panic, hallucinations, depersonalization or delirium Physiologic Effects Cannabis Ocular: conjunctivial redding, miosis, decreased IOP. CV: tachycardia, orthostatic hypotension NM: decreased muscle coordination GI/GU: dry mouth, urinary retention Duration Ethanol As ethanol level decreases within 6-24 hours 6-48 hours 3-5 days Onset: at any time Symptoms Ethanol Vivid dreams, insomnia Tremor, N/V, tachycardia, HTN Convulsions (grand-mal type) DT's Duration Cocaine/ stimulants Immediately following binge, within 1-4 hours, duration 3-4 days Symptoms Cocaine/ Stimulant Stimulant craving, intense dysphoria, depression, anxiety, and agitation. Desire for sleep, hypersomnia, increased appetite. Symptoms Opioids Shorter acting opioids ( e.g. heroin, morphine, oxycodone, hydrocodone). Onset 6-24 hrs, duration 1 week. Longer acting methadone: onset 2-4 days, duration >1 week. Symptoms Opioids GI: N/V/D and dehydration Neuro irritability, restlessness, yawning, and twitching. CV: Increase HR/BP MS: chills, increased temperature, rhinorrhea Ocular: lacrimation, dilated pupils. Duration Nicotine Within 24 hours of cessation WITHDRAWAL Symptoms Nicotine Varies with degree/duration of nicotine use: anxiety, irritability, frustration, anger, craving, decreased concentration, decreased HR, and increased appetite. WITHDRAWAL Symptoms Cannabis Withdrawal usually not noticeable except in chronic heavy use, withdrawal occurs in 24 hrs, peaks in 2-4 days, and resolves in 1-2 weeks. WITHDRAWAL Symptoms Cannabis Irritability, insomnia, restlessness, anorexia, diaphoresis, diarrhea, muscle twitching, mild increases in BP/HR. TREATMENT OF INTOXICATION SYNDROMES Psychological Medical Referral ALCOHOL INTOXICATION o Mild to moderate: no formal treatment