Pain

Question 1

Mechanism of action if diclofenac ?

Answer 1

• Reversible inhibition of COX-1 and COX-2

- decreased prostaglandin synthesis

Question 2

Indications for diclofenac ?

Answer 2

• inflammatory conditions (RA, ost op pain, acute gout)
• pain
• Pyrexia

Question 3

What drug class is diclofenac ?

Answer 3

NSAID

Question 4

Contraindications for diclofenac

Answer 4

• aspirin/NSAID hypersensitivity
• renal impairment
• peptic ulcers, active or history of recurrent
• SLE
• hyperkalaemia

Question 5

Route of elimination of diclofenac

Answer 5

Kidneys

Question 6

Side effects of diclofenac ?

Answer 6

• nausea/GI Disturbance
• dizziness
• deceased renal function
• increased blood pressure

Question 7

Possible interactions of diclofenac ?.

Answer 7

• ACEi : increased risk of renal impairment
• SSRIs: increased risk of bleeding
• B blockers, Ca channel blockers: NSAIDS antagonise hypertensive effects

Question 8

Drug class of codeine ?

Answer 8

Opiate

Question 9

How does codeine work ?

Answer 9

• Mimics endogenous opioids (e.g. Endorphins)
• acts on opioid receptors in brain (dorsal horn and grey matter) and PNS
• cause analgesic effects

Question 10

Indications for codeine

Answer 10

• mild- moderate pain
• diarrhoea
• cough suppression

Question 11

Contraindications of codeine

Answer 11

• acute respiratory depression
• paralytic ileus
• conditions associated with raided ICP and head injury as interferes with pupil light response

Question 12

Side effects of codeine

Answer 12

• Nausea and vomiting
• constipation
• dry mouth
• biliary spasm

Question 13

Possible interactions of codeine ?

Answer 13

Alcohol: enhanced hypotensive/sedative effects
Metoclopramide: antagonise effects of GI activity
cimetidine: inhibits opioid metabolism

Question 14

Elimination of codeine ?

Answer 14

Kidneys

Question 15

What drug class is morphine ?

Answer 15

Opioid

Question 16

Mechanism of action of morphine

Answer 16

• Agonist of opioid receptors (mu receptor), producing an analgesic effect by inhibiting signalling along pain pathways
• mu receptor mediates sedation, euphoria, inhibits respiration and GI Peristalsis

Question 17

Side effects of morphine

Answer 17

• constipation
• nausea and vomiting
• hypotension
• pruritis
• respiratory depression
• sedation

Question 18

Indications for morphine

Answer 18

• moderate-severe acute pain
• sever chronic pain
• intractable cough in palliative care

Question 19

Contraindications if morphine

Answer 19

• severe resp disease e.g. Asthma, COPD
• head injury/ raised ICP
• alcohol ingestion
• convulsive disorders

Question 20

Main route if elimination of morphine ?

Answer 20

Liver

Question 21

Interactions of morphine

Answer 21

• alcohol

- CNS depressants

Question 22

Mechanism of action of paracetamol

Answer 22

• inhibits COX 3 enzymes resulting in analgesic and anti pyretic effects but not anti inflammatory

Question 23

Side effects of paracetamol ?

Answer 23

• headache
• nausea
• Hepatotoxicity

Question 24

Indications for paracetamol

Answer 24

• Mild-mod pain

- fever

Question 25

Contraindications of paracetamol

Answer 25

• hepatic disease

- alcohol

Question 26

Route of elimination of paracetamol

Answer 26

Liver

Question 27

Possible interactions of paracetamol

Answer 27

Carbamazepine: increased paracetamol metabolism

Cyt p450

Question 28

What is the antidote to paracetamol overdose ?

Answer 28

N-acetylcysteine