Opioids

Question 1

indications of opioids

Answer 1

• analgesia

- antitussive (ex: codeine)

Question 2

opioid routes

Answer 2

PO, rectal, IM, IV, topical, subcut infusion, edpidural, intrathecal, intranasal, transmucosal

Question 3

opioid MOA

Answer 3

bind opioid receptors in CNS to inhibit ascending pain pathways

Question 4

what are the 3 main opioid receptors, and what do they all have in common?

Answer 4

• mu, delta, kappa
• all produce analgesia
• all have AEs of respiratory depression and slowed GI motility

Question 5

tell me about the mu receptor

Answer 5

• euphoria
• AEs: bradycardia, emesis (vomiting), pruritus (itching)
• high potential for abuse/dependence

Question 6

tell me about the delta receptor

Answer 6

• has a lower abuse potential

- no AEs unique to this receptor

Question 7

tell me about the kappa receptor

Answer 7

• can produce spinal analgesia
• AEs: miosis (excessive pupil constriction), constipation, sedation, dysphoria
• has a lower abuse potential

Question 8

common AEs of opioids (DNC)

Answer 8

• drowsiness
• nausea
• constipation

Question 9

contraindications of opioids

Answer 9

• GI obstruction
• paralytic ileus (blocked intestine)
• respiratory depression

Question 10

Boxed warnings for opioids include…

Answer 10

• increased levels with ethanol use
• addiction/abuse/misuse
• life-threatening respiratory depression
• severe AE with epidural or intrathecal admin
• neonatal opioid withdrawal syndrome
• death from accidental ingestion
• lethal medication errors
• life-threatening sedation/respiratory depression in combo with benzodiazepines or CNS depressants

Question 11

what does the beers list say about opioids?

Answer 11

cautions against taking opioids in combo with 2+ CNS active meds; if history of falls or fracture

Question 12

what are the strong mu agonists?

Answer 12

• morphine (MS Contin, Kadian)
• fentanyl (Actiq, Duragesic, Fentora, Sublimaze, Subsys)
• hydromorphone (Dilaudid, Exalgo)
• meperidine (Demerol)
• methadone
• oxycodone (Oxycontin; with acetaminophen: Percocet)

Question 13

indications of strong mu agonists

Answer 13

severe pain

Question 14

what should you watch out for with strong mu agonists?

Answer 14

• active metabolites
• morphine: can accumulate after extended dosing even if normal renal function
• meperdine: neurotoxic metabolite, especially if ↓ liver/renal function = anxiety, seizures
• hydromorphone: neuroexcitatory metabolite
• oxycodone: usually negligible levels of metabolite; often combined with acetaminophen or aspirin for additive effect

Question 15

special considerations with fentanyl

Answer 15

• do NOT use for chronic pain management if opioid naive
• physical activity/heat on the patch can increase drug delivery in a negative way, causing OD or increasing AEs
• properly dispose of patch so it is out of reach of children and pets

Question 16

what are the mild-moderate mu agonists (weak opioids)?

Answer 16

codeine and codeine combinations

Question 17

indications of mild-mod mu agonists

Answer 17

moderate pain

Question 18

tell me about codeine

Answer 18

• codeine is a prodrug, meaning it must be metabolized and converted to morphine in order to produce any effects; can get lingering metabolites
• codeine has antitussive effects, so it is used in cough syrup (abuse - purple drank, sizzurp)

Question 19

tell me about partial mixed agonists

Answer 19

• Ex: buprenorphine (Suboxone)
• Agonist with high affinity mu receptor
• Lower analgesic efficacy than other opioids (lower Emax on dose-response curve)
• Antagonist at delta and kappa receptors
• Reduce withdrawal symptoms when tx opioid dependence

Question 20

tell me about tramadol

Answer 20

• Weak mu and kappa agonist
• Inhibits reuptake of norepinephrine and serotonin (neurotransmitters in descending pain pathway)
• Less risk of dependence, but not impossible
• Risk of seizures, so avoid if hx or in combo w other drugs that can increase risk (antidepressants)

Question 21

drugs used for neuropathic pain (4)

Answer 21

• duloxetine (Cymbalta)
• pregabalin (Lyrica)
• gabapentin (Neurontin)
• amitriptyline

Question 22

duloxetine (Cymbalta)

I was tired and nauseous from my new antidepressants, and then my brother crashed his deluxe cymbals so loud it gave me a headache!

Answer 22

• Class: serotonin-norepinephrine reuptake inhibitor (SNRI), antidepressant
• AE: nausea, dry mouth, headache, dose-related fatigue and drowsiness

Question 23

pregabalin (Lyrica)

Ever since pre-K, Lyrica has gained weight and is always tired. She got dizzy going down the slide at recess and started convulsing.

Answer 23

• Class: GABA analogs, anticonvulsant

- AE: dizziness, drowsiness, headache, fatigue, peripheral edema, weight gain

Question 24

gabapentin (Neurontin) = more basic version of pregabalin

Answer 24

• Class: GABA analog, anticonvulsant
• AE: dizziness, drowsiness
• Common due to cost

Question 25

amitriptyline Am I trippin, or did riding a tricycle make me have to poop, pee, drink water, and use eye drops?

Answer 25

- Class: tricyclic antidepressant (TCA) - AE: sedation, anticholinergic effects (blurred vision, dry mouth, urinary retention, constipation) - Less common due to AE

Question 26

types of cancer pain (3)

Answer 26

- bone pain (metastases; necrosis due to radiation) - aching pain (compressed neural tissue) - visceral pain (chemo, radiation-induced fibrosis, scar tissue from surgery)

Question 27

treatment for mild cancer pain

Answer 27

- NSAIDs - acetaminophen - short-acting opioids

Question 28

treatment for moderate cancer pain

Answer 28

short-acting opioids with titration

Question 29

treatment for severe cancer pain

Answer 29

- strong opioids | - long-acting + immediate for breakthrough pain

Question 30

naloxone (Narcan)

Answer 30

- opioid antagonist/reversal agent - For acute opioid overdose or respiratory depression with therapeutic opioid doses - Competitive antagonist at μ-, κ-, and δ-receptors - Highest affinity for the μ-receptor = rapidly reversing respiratory depression and euphoria with less impact on analgesia - IV, IM, subcut, intranasal