Opioid Narcotic Analgesics Flashcards
1
Q
Endorphins
A
Mu Rc (supra-spinal analgesia)
2
Q
Dynorphins
A
Kappa Rc (spinal analgesia)
3
Q
Enkephalins/Endorphins
A
Delta Rc
4
Q
Mu opioid Rc - Full agonist
A
- Fentanyl (more potent)
2. Morphine
5
Q
Partial agonist (Mu)/mixed (Mu/K/delta)
A
- Buprenorphine (partial agonist/mixed)
2. Pentazocine (mixed)
6
Q
Mu opioid Rc - antagonist
A
- Naloxone
- Naltrexone
BOTH inhibit heroin, morphine, fentanyl –> ANTIDOTE for opioid overdose
7
Q
Tolerance to morphine
A
Response dec over time –> increase dose or different opioid
NO TOLERANCE TO - miosis, constipation
Contraindication - brain injury, emphysema
8
Q
Group 1
Full agonists
Parenteral/Oral
A
- Morphine (low oral:parenteral ratio)
- Methadone (high O:P ratio)
- Meperidine
- Hydromorphine
- Oxymorphine
- Levorphanol (high O:P ratio)
9
Q
Group 2
Full agonists
Short acting
A
- Fentanyl
- Sufentanil (Mu, K, delta)
- Remifentanyl - VERY short acting
- Alfentanil
This group is 100x more potent than morphine and methadone
10
Q
Group 3
Partial agonists
A
- Codeine - high O:P ratio; low efficiency; give higher dose
- Hydrocodone - usually given with acetaminophen
- Oxycodone - usually given with acetaminophen
11
Q
Morphine
A
CYP 3A4 = normorphine (INACTIVE)
UGT 1A1/2B7 = Morphine-3-glucuronide and Morphine-6-glucuronide (ACTIVE)
Dehydrogenase = Hydromorphone (ACTIVE)
12
Q
Methadone
A
- useful for withdrawal/maintenance, detoxification
- affects electrical conduction of heart - QT interval prolonged in overdose/long term trt
- block K channel –> delayed repol (HERG channels)
- longer half life than morphine
13
Q
Meperidine
A
- eye: dilation
- Normeperidine (toxic) accumulates –> seizures
Fentanyl –> meperidine –> morphine
(faster –> slower onset)
14
Q
Remifentanyl
A
- childbirth analgesia
- metab by plasma and tissue esterases (rapid in fetus)
- RAPID onset/SHORT acting
15
Q
Fentanyl (lollipop)
A
- RAPID onset/SHORT duration (Lipophilic)
- transmucosal
- used for ‘break through pain’ due to morphine
- transdermal patch delivery (slow onset)
- NO active metabolite (like Hydromorphone and oxymorphone)