Analgesics 2

Question 1

Opioids

Answer 1

Opioid agonist at the mu opioid receptor mainly and kappa as well.
Pure opioid agonist: Work on both receptors. Morphine, codeine
Partial: agonist on one, antagonist on other receptors. Provides a limited effect to balance out. Buprenorphine (drug abuse, harder to OD on)
Opioid antagonists: pure antagonist on both, reverse opioids

Question 2

Opioid Agonists

Answer 2

IND: Pain
MOA: Pure mu and kappa agonists, inhibits ascending pain pathways
BOX: Potential for abuse, addiction, misuse, OD
Risk evaluation and mitigation strategy (REMS)
Life threatening respiratory depression
Neonatal opioid withdrawal; treat with opioids for ~30 days
Risk of use with Benzos or other CNS depressants; profound sedation and respiratory depression
CON: Significant baseline respiratory depression, hypercapnia, GI
ADR: CNS effects, respiratory depression, GI, Miosis, urine retention

Question 3

Tolerance and Physical Dependence

Answer 3

Tolerance: When a larger dose is required to produce the same response as a smaller dose used to. Takes time to develop. Therapeutic effects requires smaller doses than constipation and miosis. Cross reaction with other opioids but NOT other drugs like BENZOS, give regular benzo dose.

Physical Dependence: Withdrawal syndrome when drug use is abruptly d/c. Results from adaptive cellular changes. Varies based on half life of drugs. VERY unpleasant but NOT usually deadly. Sweating, yawning, anorexia, irritability, n/v/d. 7-10 days at most.

Question 4

Abuse Liability

Answer 4

High in opioids. Abuse is using them just to get a pleasurable experience, not to prevent badness (Physical dependence). Can be both tho.

Question 5

Morphine

Answer 5

IND: Pain
MOA: Pure
BOX: Opioids +
Risk with neuroaxial administration (Duramorph); respiratory depression
Ethanol use (XR caps); avoid
Risk of medication errors: mg v mL could kill someone
CON: MOAI
ADR: Opioids

Question 6

MME

Answer 6

Morphine Milligram Equivalent
Significant increase in respiratory depression and harm as MMEs increase
Calculate conservatively/round down
Always prescribe lowest possible dose
Careful justification for doses >50 MME
Higher dose does not equal longer pain reduction

Question 7

Hydrocodone

Answer 7

Norco
IND: Pain
MOA: Opioid
BOX: Opioid +
Cytochrome P450 3A4 Inhibitors; will increase Norco concentrations
CON:
ADR:
Equipotent as morphine

Question 8

Oxycodone

Answer 8

IND: Pain
MOA: Opioid
BOX: Opioid +
Medication errors can lead to death
Cytochrome P450I’s
CON:
ADR:
MME: 1.5

Question 9

Hydromorphone

Answer 9

Dilaudid
IND: Pain
MOA: Opioid
BOX: Opioid
CON:
ADR:
MME: 4

Question 10

Oxymorphone

Answer 10

IND: Pain
MOA: Opioid
BOX: Opioid
CON:
ADR:
3

Question 11

Codeine

Answer 11

IND: Pain and cough
MOA: Cough Suppressant in the medulla. Converted to Morphine by CYP2D6
BOX: Ultra rapid metabolism; life threatening respiratory depression. ( Most cases after tonsil/adenoidectomy) d/t CYP2D6 Polymorphism.
Cytochrome P450 3A4 I’s
CON: Peds under 12, post-op pain in peds under 18 who’ve had tonsil/adenoidectomy. MAOIs.
ADR:

Question 12

Fentanyl

Answer 12

IND: Pain. 100x as potent as morphine
MOA: Opioid
BOX: Med errors.
REMS for buccal and transdermal presentation
CON:
ADR: Peripheral edema. Hyperhidrosis/dehydration, Application site erythema (topical patch products)

Question 13

Methadone

Answer 13

IND: Opioid Use Disorder, pain, opioid withdrawal
MOA: Opioid agonist and NMDA receptor antagonist
BOX: Life threatening QT prolongation and serious arrhythmias.
Code of Federal Regulations for detox administration
CON:
ADR: Arrhythmias

Question 14

Meperidine

Answer 14

IND: Pain, post op shivering/rigors
MOA:
BOX: MAOIs
CON: MAOIs
ADR: Myoclonus, seizures, delirium psychosis d/t active metabolite. Histamine release; hypersensitivity. Serotonin syndrome

Question 15

Tramadol

Answer 15

IND: Pain
MOA: Opioid agonist and SNRI activity
BOX: Ultra rapid metabolism, avoid in under 12 or under 18 with t/a-ectomy
CON: Peds from box. MAOIs
ADR: Serotonin syndrome

Question 16

Buprenorphine

Answer 16

IND: Pain, opioid use disorder
MOA: Mu partial agonist, kappa antagonist at opiate receptors in the CNS. Analgesic plateau at higher doses, then behaves as an antagonist; prevents profound euphoria and pain analgesia
BOX: n/a
CON:
ADR: Injection site rxns, sedation

Question 17

Nalbuphine

Answer 17

IND: Pain, Sx anesthesia supplement, opioid induced pruritis
MOA: Mu partial ANTAGONIST, kappa AGONIST. Opposite of Buprenorphine, still does the plateau
BOX: n/a
CON:
ADR: Sedation

Question 18

Naloxone

Answer 18

Narcan
IND: Opioid OD, reversal of respiratory depression w/therapeutic opioid doses, opioid use disorder, opioid-induced pruritis
MOA: Opioid receptor antagonist
BOX: none
CON: none
ADR: Agitation, aggression, intense return of pain

Question 19

Naltrexone

Answer 19

IND: Alcohol use disorder, opioid use disorder, pruritis
MOA: Opioid receptor antagonist
BOX:
CON: Current physiological dependence or current use of opioids, acute opioid withdrawal, failure to pass naloxone challenge, or positive urine screen for opioids. Risk of withdrawals and takes 28 days if injected.
ADR: Syncope, GI, Increased AST/ALTs, Injections site rxns, arthralgias, joint stiffness