Analgesics

Question 1

What different analgesic medications are there?

Answer 1

• Paracetamol
• NSAID
• Opioids Agonist
• Opioid Antagonist
• Synthetic Opioid

Question 2

What are the 4 steps of the pain pathway?

Answer 2

• Transduction
  
  • Inflammatory mediaters are released and activate
    the first neuron , sends message for pain
• Transmission
  
  • Neurons are firing (A delta fast, C slow)
• Perception of pain
• Modulation
  
  • Alters a pain signal as it is transmitted along the pain pathway

Question 3

How many opioid receptors are there and what are they called?

Answer 3

Mu
Kappa
Delta

Question 4

What is an example of an opioid agonist?

Answer 4

Morphine
Loperamide
Codeine

Question 5

What is the indication of use for opioid medications, specifically Morphine?

Answer 5

Typically, Opioids are prescribed for the short-term treatment of moderately severe or severe pain, such as pain experienced following surgery or an injury. They can be prescribed for palliative care and chronic pain.

Question 6

What is the MOA for opioid medications?

Answer 6

Spinal level: stimulates opioid receptor and inhibits substance p release from the dorsal horn neurons.

Supraspinal: closes dorsal horn gate inhibiting afferent transmission to cortex. Alter pain perception and response.

Stimulates mu receptors

Question 7

What are some adverse drug reactions associated with Opioid medications?

Answer 7

Respiratory depression, Excessive sedation, Dysphoria, Constipation, Nausea & vomiting, Tolerance and Dependence, (histamine release) itch, bronchoconstriction, urinary retention, Euphoria

Question 8

What patient education would you provide to someone who is on opioid medications?

Answer 8

• Do not drink alcohol
• This medication may be addictive with prolonged use, talk to Dr. if you feel it isn’t working for you anymore
• Has sedation effects and may make you more sleepy than normal
• This medication can make you constipated

Question 9

What are some cautions/contraindications associated with opioids?

Answer 9

Interacts with alcohol, Monoamine oxidase inhibitor. Opioid antagonist. Avoid in head injury

Question 10

What are the KEY monitoring requirement associated with opioids?

Answer 10

Bowels
Resp rate
Sedation
Nausea/Vomiting (input/output)

Question 11

What slow releasing types of morphine are available?

Answer 11

m-Elson capsules, LA Morph tablets

Question 12

What are some immediate releasing type of morphine which are available?

Answer 12

Severdol tablets or RA Morph solution

Question 13

What must be available for IV morphine administration?

Answer 13

Naloxone and oxygen

Question 14

How do morphine infusions occur? and what monitoring requirements are required?

Answer 14

Through a pump. Monitoring of respiratory rate as well as sedation recorded hourly throughout the infusion as can cause respiratory depression and sedation.

Question 15

What is the indication of use for Loperamide?

Answer 15

Acute and chronic diarrhoea

Question 16

What is the MOA for Loperamide?

Answer 16

Loperamide is synthetic opioid that binds to the opiate receptor in the gut wall. Consequently, it inhibits the release of acetylcholine and prostaglandins, thereby reducing propulsive peristalsis, and increasing intestinal transit time. Loperamide increases the tone of the anal sphincter, thereby reducing incontinence and urgency. Slows down the movement of the gut

Question 17

What are some adverse drug reactions associated with Loperamide?

Answer 17

Nausea, abdominal cramps, dizziness, drowsiness, urticaria (a raised, itchy rash that appears on the skin)

Question 18

What are some contraindications/cautions associated with Loperamide?

Answer 18

Conditions where inhibition of peristalsis should be avoided; where abdominal distension develops or in conditions such as active ulcerative colitis or antibiotic-associated colitis. Ensure appropriate use of fluid and electrolyte replacement; in acute diarrhoea only use for short-term symptomatic management

Question 19

What patient education would you provide to someone on Loperamide?

Answer 19

• Loperamide can be taken before or after food.
• If you forget to take a dose, just take a dose after the next time you go to the toilet with diarrhoea. Do not take two doses together to make up for a missed dose.
• Make sure you drink plenty of water or electrolyte replacement drinks because diarrhoea can make you dehydrated.

Question 20

What opioid antagonist can reverse opioid overdose?

Answer 20

Naloxone

Question 21

What is the MOA for Naloxone?

Answer 21

Attach to opioid receptor within the nervous system but not stimulate them = prevention of opioid effects.

Question 22

What are some adverse drug reactions associated with Naloxone?

Answer 22

Nausea, vomiting, hypotension, hypertension, tachycardia, headache, dizziness, dry mouth

Question 23

What is an example of a Synthetic Opioid?

Answer 23

Tramadol

Question 24

What is the indication of use for Tramadol?

Answer 24

Moderate to severe pain; post-operative pain

Question 25

What is the MOA for Tramadol?

Answer 25

Tramadol is a synthetic opioid agonist resulting in inhibition of ascending pain pathways in the brain and spinal cord, altering the perception and response to pain. Tramadol also inhibits re-uptake of noradrenaline and serotonin which may contribute to its analgesic activity. Stimulates mu receptors

Question 26

What are some adverse drug reactions associated with Tramadol?

Answer 26

Nausea, vomiting, constipation, dry mouth, dyspepsia, biliary spasm, bradycardia, tachycardia, palpitation, oedema, postural hypotension, mood changes, dizziness, confusion, drowsiness, sleep disturbances. Risk of serotonin toxicity Less risk of respiratory depression, euphoria, or addiction. Reduced seizure threshold

Question 27

What are some contraindications/precautions associated with Tramadol?

Answer 27

reduced seizure threshold, risk of serotonin toxicity (contraindicated when on MAOis or history of seizures). Avoid if creatinine clearance within renal function less than 10 mL/minute

Question 28

What is a example of a Non-Steroidal anti-inflammatory drugs (NSAIDs)

Answer 28

Ibuprofen

Question 29

What is the indicator of use for NSAIDS (Ibuprofen)?

Answer 29

Analgesic for mild to moderate pain, fever, anti-platelet, anti-inflammatory and anti-pyretic

Question 30

What is the MOA for NSAIDs?

Answer 30

Inhibit cyclo-oxygenase (COX) enzyme and therefore inhibits production of prostaglandins, Prostaglandin have several psychological actions including the mediation of pain, inflammation and increasing body temperature.

Question 31

What are some contraindications for NSAIDs?

Answer 31

- Renal impairment - Asthma - Known AKI or peptic ulcers

Question 32

What are some adverse drug reactions associated with NSAIDs?

Answer 32

Gastric irritation due to COX 1 decreasing mucus production, peptic ulceration/bleeding, Reduction in GFR leading to fluid retention, Prolonged bleeding time, increased risk of MI & Asthma attacks

Question 33

What patient education would you provide to someone on NSAIDs?

Answer 33

- Advise patients to take ibuprofen with a full glass of water and with food, and to remain in an upright position for 15– 30 min after administration. - Educate patient that taking higher than recommended doses does not provide increased pain relief but may increase incidence of side effects. Use lowest effective dose for shortest period of time, especially in the elderly. Avoid the concurrent use of alcohol, aspirin, paracetamol as these can alter the effect of the drug. - Inform patients ADRs. Inform Health care professional if rash, itching, tinnitus, weight gain/oedema, epigastric pain, dyspepsia, black stools, hematemesis, persistent headache. - Paediatrics: Advise parents or caregivers not to administer ibuprofen to children who may be dehydrated (can occur with vomiting, diarrhoea, or poor fluid intake); dehydration increases risk of renal dysfunction. - Advise female patients to notify health care professional if pregnancy is planned or suspected.

Question 34

What is the indicator of use for paracetamol (acetaminophen)?

Answer 34

Fever, migraine, tension headache, pain (non-inflammatory origin), osteoarthritis * Weak anti-inflammatory effect

Question 35

What is the MOA for paracetamol?

Answer 35

unclear, has both local action (COX inhibition) and central action (inhibition of prostaglandin synthesis in the CNS)

Question 36

What are some adverse drug reactions associated with paracetamol?

Answer 36

ADR's are RARE: liver impairments, cause malaise, overdose can cause hepatic necrosis

Question 37

What is an adjuvant analgesic and can paracetamol be one?

Answer 37

Yes it can. Adjuvant analgesic are medication that is not primarily designed to control pain but can be used for this purpose. (Antidepressants, Anticonvulsants, Antihistamines, Corticosteroids)

Question 38

What patient education would you provide to someone who is taking paracetamol?

Answer 38

Lots of other Over The Counter medications contain Paracetamol in them, e.g., cold n flu medications. – caution with exceeding daily dose (4g for an adult).

Question 39

How do you reverse Acute Hepatotoxicity for a paracetamol-induced overdose?

Answer 39

hepatotoxicity can be reversed with acetylcysteine (parvalax), this drug works by preventing the hepatotoxic metabolites of Paracetamol from working.

Question 40

What is the WHO analgesic ladder? Explain each step

Answer 40

PAIN: Assess, pain evaluation, individual parameters (age, concurrent conditions, drug history, etc.) !! First step. Mild pain (1-3 pain): non-opioid analgesics such as non-steroidal anti-inflammatory drugs (NSAIDs) or acetaminophen with or without adjuvants !! Second step. Moderate pain (4-6 pain): weak opioids (hydrocodone, codeine, tramadol) with or without non-opioid analgesics and with or without adjuvants !! Third step. Severe and persistent pain (7-10 pain): potent opioids (morphine, methadone, fentanyl, oxycodone, buprenorphine, tapentadol, hydromorphone, oxymorphone) with or without non-opioid analgesics, and with or without adjuvants * Monitor to prevent ADR's (constipation, Nausea and vomiting, sedation, Respiratory depression)

Question 41

What is the difference between COX 1 and COX 2 enzyme?

Answer 41

COX 1 is focused on platelets and homeostasis COX 2 is focused on inflammation