Narcotic Analgesics

Question 1

Describe the WHO pain Ladder.

Answer 1

Mild Pain: non-opioid +/- adjuvant
Moderate Pain: Weak opioid +/- non-opioid +/- Adjuvant
Severe pain: Strong opioid +/- non-opioid +/- Adjuvant

Question 2

What are the 3 major opioid receptor types?

Answer 2

µ (Mu), δ (Delta) and κ (Kappa)

Question 3

Where are the 3 different sites of opioid receptors regulating pain located?

Answer 3

Brain (Supraspinal analgesia)
Spine (spinal analgesia)
Peripheral nociceptive terminal (peripheral analgesia)

Question 4

What opioid receptors type are responsible for Supraspinal analgesia, spinal analgesia & peripheral analgesia?

Answer 4

µ - Supraspinal analgesia
δ - spinal analgesia
κ - peripheral analgesia

Question 5

Elderly patients require a ______ (lower/higher) dose to achieve effective pain relief than younger patients

Answer 5

lower

Question 6

Neurpatic pain usually requires ______ (lower/higher) opioid doses than nociceptive pain.

Answer 6

higher

Question 7

______ (lower/higher) doses are usualy requireds for continuous maintenance of pain relief than administration in responce to recurrence of pain

Answer 7

lower

Question 8

Describe the “dosing to effect” for opioid treatment

Answer 8

opioid analgesics should be started at a low dose and carefully tiratredf until an adequate level of analgesia is obtained, or until persistent and unacceptable side effects warrent an reevalutation of therapy

Question 9

What are the clinical uses of opioid agonists? (Codeine, morphine, pethidine, fentanyl, diphenoxylate)

Answer 9

Analgesia: Codeine, morphine, pethidine
Anaesthetic adjuvant: Fentanyl
Cough suppressant / antitussive:Codeine
Anti-diarrhoeal: Diphenoxylate

Question 10

What type of opioid are morphine, methadone, pethidine and fentanyl?

Answer 10

strong µ agonist ( weaker δ & κ agnosit for morphine only)

Question 11

What is the difference between methadone and fentanyl?

Answer 11

Methadone is long acting (>24 hrs) amd fentanyl is short-acting (anaesthetic adjuvant)

Question 12

What strong opioid agonists are there?

Answer 12

Morphine, Fentanyl, Pethidine and Methadone

Question 13

Which strong opioid agonist can cause dry mouth, blurring of vision?

Answer 13

Pethidine due to anti-muscarinic actions

Question 14

What are some moderate opioid agonist?

Answer 14

Codeine and tramadol

Question 15

What type of opioid are Codeine and tramadol?

Answer 15

Codeine: weak µ & δ agonist
Tramadol: weak µ agonist

Question 16

What are the actions of opioid in the nucleus tractus solitarius and nucleus ambiguus?

Answer 16

Reduce responces to CO2 and suppress voluntary breathing

Question 17

What are some common adverse effects of opioid?

Answer 17

1. Nausea/ vommiting
2. Drowsiness
3. Constipation due to reduced gastrointestinal mobility ( esp with chronic use)
4. Miosis (pinpiont pupil is a disgnostic deature of opioid overdose) However, mydriasis could occer due to hypoxia
5. urinary retentation due to increased bladder sphincter tone
6. postural hypotension and bradycardia
7. Immunosuppresent

Question 18

What is a major contraaindication of morphine?

Answer 18

Asthma, morphine can also trigger histamine release, causing bronchocontriction

Question 19

What are some opioid withdrawal symptoms?

Answer 19

Anxiety, irritabilityy, chills, hot flushes, joint pain, nausea, vomiting, diarrohea

Question 20

What is naloxone?

Answer 20

opioid antagonists, used to counteract opioid overdose; must be carefuly to avoid potentially fatel withdrawal syndrome.