Analgesics

Question 1

Paracetamol

Answer 1

0.5-1 g every 4-6 hours to a max of QDS.
IV or PO.
Specific doses for children

Question 2

Ibuprofen

Answer 2

300-400 mg 3-4 times daily.

Question 3

Diclofenac

Answer 3

75-150 mg daily in 2-3 divided doses

Question 4

NSAID cautions

Answer 4

Allergy to NSAID
Coagulation defects
Poor renal function
Arterial disease

Question 5

NSAID adverse effects

Answer 5

GI bleed
Hypersensitivity 
Headache
Blood disorders 
Renal failure 
Worsening of asthma

Question 6

Examples of Cox-2 inhibitors

Answer 6

Celecoxib
Etoricoxib
Parecoxib

Question 7

Paracetamol cautions

Answer 7

Liver dysfunction
Alcoholism
Malnutrition

Question 8

Paracetamol side effects

Answer 8

Malaise
Skin reactions inc Stevens Johnson
Blood disorders (penias)

Question 9

Tramadol dose and route

Answer 9

PO- 100 mg initially then 50-100 mg every 4-6 hours

IM/IV 50-100 mg every 4-6 hours

Question 10

Tramadol cautions

Answer 10

Impaired consciousness
Excessive bronchial secretions
Epilepsy / seizures

Question 11

Tramadol side effects

Answer 11

General opioids
Malaise
Diarrhoea 
Gastritis
Flatulence

Question 12

Codeine dose and route

Answer 12

PO 30-60 mg every 4 hours to a max of 240 mg daily.

IM 30-60 mg every 4 hours when necessary

Question 13

Codeine cautions

Answer 13

Cardiac arrhythmia
Acute abdomen
Gallstones
Contraindicated in ultra-rapid codeine metabolisers

Question 14

Codeine side effects

Answer 14

Opioids 
Abdo pain
Anorexia
Seizures
Malaise

Question 15

Morphine dose and Route

Answer 15

Acute pain - subcutaneous injection up to 10 mg.
Slow IV-5 mg every 4 hours
PCA

Question 16

Fentanyl dose and route

Answer 16

Transdermal

Question 17

Orthodoxe dose and Route

Answer 17

PO - 50-150 mg every 4 hours

IM 25-100 mg 1 hour pre op or post op every 2-3 hours as necessary

Question 18

Opioid cautions

Answer 18

Impaired resp function
Hypotension
Urethral stenosis 
Myasthenia gravis 
Prostatic hypertrophy 
Bowel disorder
Biliary tract disease

Question 19

Opioid side effects

Answer 19

Nausea
Biliary spasm 
resp depression 
Bradycardia/tachycardia 
Constipation

Question 20

Pethidine

Answer 20

• Synthetic opioid which is structurally different from morphine but which has similar actions. Has 10% potency of morphine.
• Short half life and similar bioavailability and clearance to morphine.
• Short duration of action and may need to be given hourly.
• Pethidine has a toxic metabolite (norpethidine) which is cleared by the kidney, but which accumulates in renal failure or following frequent and prolonged doses and may lead to muscle twitching and convulsions. Extreme caution is advised if pethidine is used over a prolonged period or in patients with renal failure.

Question 21

Neuropathic pain

Answer 21

National Institute of Clinical Excellence (UK) guidelines:
•First line: Amitriptyline (Imipramine if cannot tolerate) or pregabalin
•Second line: Amitriptyline AND pregabalin
•Third line: refer to pain specialist. Give tramadol in the interim (avoid morphine)
•If diabetic neuropathic pain: Duloxetine

Question 22

Morphine

Answer 22

• Short half life and poor bioavailability.
• Metabolised in the liver and clearance is reduced in patients with liver disease, in the elderly and the debilitated
• Side effects include nausea, vomiting, constipation and respiratory depression.
• Tolerance may occur with repeated dosage