Pain medications

Question 1

A patient is on 5mg IR morphine every 4h.

How much and how often is his PRN dose

Answer 1

Same dose (5mg)
Give 1-2hrly

Question 2

A patient is on 5mg IR morphine every 4h, and taking PRN morphine 6 times during the day.

What should his new 4h dose be?

Answer 2

Calculate previous 24h dose + PRN
= 56 + 56
= 60mg in 24h

Thus he should get 10mg every 4h

Question 3

A patient is on 30mg MR morphine every 12h.

How much and how often is his PRN dose

Answer 3

PRN dose is 1/6 to 1/10 of 24h dose

6-10 mg (1/6 to 1/10 of 60mg)
Give 1-2hrly

Question 4

What drug is used to reverse opiate toxicity

Answer 4

Naloxone

Question 5

In palliative care, what drug is used for pain/ breathlessness in

• normal kidney function
• reduced kidney function

Answer 5

Normal kidney function
MORPHINE

Reduced kidney function
ALFENTANIL

Question 6

In palliative care, what drug is used for respiratory secretions in

• normal kidney function
• reduced kidney function

Answer 6

Normal kidney function
HYOSCINE HYDROBROMIDE

Reduced kidney function
HYOSCINE BUTYLBROMIDE

Question 7

In palliative care, what drug is used for nausea in

• normal kidney function
• reduced kidney function

Answer 7

Normal kidney function
CYCLIZINE

Reduced kidney function
HALOPERIDOL

Question 8

In palliative care, what drug is used for agitation in

• normal kidney function
• reduced kidney function

Answer 8

for both:

MIDAZOLAM

Question 9

Contraindications to prescribing paracetamol

Answer 9

1. liver failure

2. severe renal impairment (eGFR <30)

Question 10

Contraindications to prescribing NSAIDs

Answer 10

1. Peptic ulcer/ GI bleed
2. Liver/ renal impairment
3. Clotting disorders
4. Hypersensitivity (eg asthma)
5. Pregnancy
6. Hypovolemia

Question 11

Increased risk of MI and stroke are associated with which COX enzyme

Answer 11

COX2

Question 12

Contraindications to prescribing all opioids

Answer 12

1. Respiratory depression
2. Comatose
3. Raised ICP/ head injury

Question 13

What drugs cannot be given with tramadol?

Why?

Answer 13

SSRI/SNRI

Risk of serotonin syndrome.
Tramadol also blocks serotonin/ norepinephrine reuptake

Question 14

Which drug is normally given for post-operative pain?

Answer 14

Oxycodone (lower risk of opiate toxicity)

Question 15

What drugs are given for neuropathic pain? Which are 1st line

Answer 15

Amitryptiline, Gabapentin, Pregabalin, Duloxetine

Amitryptiline and Pregabalin are 1st line

Question 16

What drugs are used for bowel colic/ bladder spasm

Answer 16

Hyoscine butylbromide (buscopan)

Question 17

What drugs are used for bowel colic/ bladder spasm

Answer 17

Hyoscine butylbromide (buscopan)

Question 18

What drugs are used for muscle spasm

Answer 18

Baclofen, Diazepam

Question 19

What drugs are used for bone pain

Answer 19

Bisphosphonates

eg Zolendronic acid

Question 20

Mechanism of action of bisphosphonates

Answer 20

Encourage apoptosis of osteoclasts, to slow bone loss

Question 21

Mechanism of action of hyoscine butylbromide

Answer 21

Antimuscarinic

Question 22

4 signs of opioid toxicity

Answer 22

1. Myoclonic jerks
2. Pin-point pupils
3. Hallucinations, confusion
4. Severe respiratory depression

Question 23

When converting SC morphine to SC alfentanil, how much to give

• routine
• breakthrough pain

Answer 23

1/15 for routine

1/10 for breakthrough pain

Question 24

Side effects of corticosteroids

Answer 24

• Easy bruising
• Muscle wasting, atherosclerosis
• Euphoria, depression, psychosis
• Thinning skin/poor wound healing
• Hyperglycaemia
• Osteoporosis
• Cushing’s like syndrome