Opioids

Question 1

What is the opiod toxidrome?

Answer 1

· Miosis, respiratory depression, CNS depression

Question 2

How does clonidine work for opiate withdrawal

Answer 2

Clonidine binds to alpha 2 adrenergic receptos which stimulates K+ efflux the same way that opioids do

Question 3

How are opioids metabolized?

Answer 3

• Hepatically (has implications for liver failure – prolonged half life)

Question 4

How are opioids eliminated?

Answer 4

renally

Question 5

What opioids are associated with seizures?

Answer 5

• Meperidine (its metabolitem: normeperidine)

Propoxyphene

Question 6

What are the half-lives of heroin and methadone? How does this affect the onset of withdrawal symptoms after cessation?

Answer 6

Heroin: T1/2= 30 min WD after 4-6 hrs

Methadone: T1/2 15-40hr

Question 7

What route of opioid abuse is associated with spongiform leukoencephalopathy?

Answer 7

“Chasing the dragon” – Inhalation of heated heroin

Question 8

List symptoms of spongiform leukoencephalopthy

Answer 8

• Psychomotor retardation
• Dysarthria
• Ataxia
• Tremor
• Other neurologic abnormalities

Question 9

What opioids can precipitate the serotonin syndrome?

Answer 9

Meperidine

Question 10

What opioid does not cause meiosis

Answer 10

meperidine (demerol)

Question 11

What mechanisms contribute to nausea and vomiting caused by opioids?

Answer 11

• Delayed gastric emptying
• Direct stimulation of chemoreceptor trigger zone
  Vestibular stimulation

Question 12

What is the differential for opiate intoxication?

Answer 12

• Clonidine
• Tramadol
• VPA
• GHB
• Sedative hypnotics
• Brainstem or pontine infarct

Question 13

What is the IV dose of naloxone?

What is the dose of an infusion

Answer 13

• Start at 0.04mg and titrate to respirations, fentanyl long acting oxycontin may require doses up to 10mg

2/3 the initial effective dose/hr

need to monitor for 2+ hrs after naloxone b/c of its short half life (30-80 min avg 60 min)