Opioid Analgesics I-II Flashcards
Name 2 methadone family (phenyheptamines) agonists. What receptor do they act on?
- methadone and relatives
- propoxyphene (Darvon)
- *** all are μ-receptor agonists
Where in the body does opioid tolerance NOT occur?
- in the GI tract
- eyes (miosis)
Name the endogenous opioid class:
- short acting; not systemic
- released at synapses (NTs)
- derived from pro-enkephalins
- brain and spinal cord
enkephalins
What is the tx for opioid OD?
- naloxone (Narcan)
- Naltrexone (Revia)
Name the an endogenous opioid class:
- new family
- μ-receptor selective
endomorphins
What is dependence?
the psych need to use the drug to maintain homeostasis and prevent withdrawal effects
When are opiates contraindicated?
- respiratory problems of any kind
- head injury
- HTN
- shock
- excessive histamine release
- hypothyroidism
- hepatic dysfunction
Name the endogenous opioid class:
- larger
- NTs and neurohormones
- derived from POMC
- hypothalamus and pituitary (stress)
endorphins
What is an endorphin?
- an endogenous opioid class
- larger
- NTs and neurohormones
- derived from POMC
- hypothalamus and pituitary (stress)
How are opioids used as cough suppressants?
they inhibit the cough center of medulla
When are opiates indicated?
- relief of moderate to severe pain (malignancy, post-op, obstetrics)
- cough
What is a dynorphin?
- an endogenous opioid class
- unk role
- derived from prodynorphin
Name 3 meperidine and other phenypiperdine agonists. What receptor do they act on?
- meperidine (Demerol)
- loperimide (Imodium)
- fentanyl and relatives
- *** all are μ-receptor agonists
Name the 4 classes of endogenous opioids.
- enkephalins
- endorphins
- dynomorphins
- endomorphins
What is the effect of opioid binding in the chemorecptor trigger zone (CTZ)?
nausea/vomiting (except overdose levels)
What is the life-threatening SE of opioids?
respiratory depression
Name the endogenous opioid class:
- unk role
- derived from prodynorphin
dynorphins
Name 8 opioid phenanthrene agonists. What receptor do they act upon?
- Morphine
- Heroin
- Codeine
- Hydromorphone (Dilaudid)
- Oxymorphon
- Oxycodone (oxycontin, Percocet)
- Hydrocodone (Vicodin)
- Tramadol (ultram)- also blocks MAO uptake
- *** μ-receptor agonists
What are the 3 receptors that opioids can bind to? How often are they used as drug targets? What kind of receptors are they?
- μ (most),
- δ (no drugs avail)
- κ (some)
- all are GTP receptor types (Gi and Go)
Why do opioids cause miosis?
they excite the Edinger-Westfall nucleus
What is tolerance?
- prior dose doesn’t produce same effects
- increased dose needed to produce same effects
How do opioids cause respiratory depression?
they bind to brainstem nuclei –> decrease sensitivity of CO2
What 3 other drugs can opioids interact with? What is the effect?
- Barbs (additive)
- Phenothiazines (antipsychotics- can increase SEs)
- MAOIs/tricyclic antidepressants (increase SEs, cause excitation, delirium, SZs)
What is an endomorphin?
- an endogenous opioid class
- new family
- μ-receptor selective
What is an enkephalin?
- an endogenous opioid class
- short acting - not systemic
- released at synapses (NTs)
- derived from pro-enkephalins
- brain and spinal cord
Name 2 opioid antagonists. What are they used for?
- Naloxone (Narcan)
- Naltrexone (Revia)
- *** these reverse opioid OD
What is the effect of opioid binding in the GI tract?
- binds at smooth muscle –> constipation, spasm
- biliary spasm/pain/pressure –> stones
- bind at ureters/bladder –> increase tone and contraction
Name 4 mixed opioid agonists/antagonists and partial agonists. What receptor do they act upon?
- buprenorphine (*** partial μ-receptor agonist)
- pentazocine (k agonist, μ antagonist)
- butorphanol (k agonist)
- nalbuphine (k agonist, μ antagonist)
