Exam 3 - Lecture 31, Opioids

Opioid use disorder, based on DSM

Withdrawal of opioid drug or blockade of its action by antagonist results in reduction of opioid receptor stimulation subsides when endogenous opioid system recovers normal function

Physiological features identical whiter they’re due to discontinuation of drug or due to antagonist admin

occurs within minutes of antagonist admin and lasts only 2 hours

after discontinuation of opioid admin is protracted

Lacrimation (watery eyes), rhinorrhea (runny nose), yawning, sweating

restless sleep (yen)

goose-flesh, mydriasis, agitation, tremors

Peak of withdrawal symptoms Insomnia, chills, cramps, vomiting, diarrhea, leg cramps, sweating, elevated HR and BP, fluid depletion (can lead to death if severe)

Withdrawal syndrome complete

drug will abruptly terminate above symptoms and restore “normalcy”

Available as morphine sulfate and morphine HCL Analgesic dose 10mg/70kg im or sc provide analgesia for 70% patients Orally only 1/6 - 1/15 as effective as im or sc

Oral potency is 2/3 of parenteral, so oral admin more practical than morphine Lower analgesic potency than morphine but can be enhanced by combo with aspirin Less abuse potential, slower tolerance develop, less sedation and GI effects than morphine Used as analgesic and anti-tussive

Synthetic codeine analog Mechanism: Blockade 5HT reuptake with weak m-opioid agonist No respiratory depressant or Cardio effects Side effects: Seizures Risk of 5HT syndrome

5 - 10 times more potent than morphine with greater respiratory depressant action Widely prescribed, high abuse potential

Preferred by addicts, must euphoric High abuse Not legally made in US

found in Hycodan, Vicodin, Zohydro

combined w/ aspirin = Percodan combined w/ acetaminophen = Percocet Often used in Slow-release form (Oxycontin) for chronic pain subject to widespread abuse, addicts crush for rapid high

Respiratory depression Nausea and vomiting Pruritus Urticaria Constipation Urinary retention Delirium Sedation Myoclonus Seizures

Hypogonadism Immunosuppresion Increased feeding Increased Growth hormone secretion Withdrawal effects tolerance, dependence Abuse, addiction Hyperalgesia Impairment while driving

“equianalgesic doses” Less potent than morhpine, more rapid onset of analgesia and shorter duration Less constipation and urinary retention than morphine No anti-jussive action Tolerance and physical dependence of opioid type do develop with chronic use Sever reactions w/ patients taking MAOI

Very potent, used in neurolept analgesia or manage of severe, chronic pain in cancer patient Can cause fatal hypoventilation in children and adults

Transdermal version of fentanyl used as means for chronic pain control

lozenge that dissolves in mouth, used for break-through cancer pain