Analgesics

Question 1

1) Paracetamol and aspirin (and other NSAIDs) are suitable for what type of pain?
2) what type of pain are opioids particularly suitable for treating?

Answer 1

1) particularly suitable for in musculoskeletal conditions

2) Opioid more suitable for moderate to severe pain, particularly of visceral origin

Question 2

1) How is pain associated with mild sickle-cell crises is managed?
2) How it it managed in severe sickle-cell crises?
3) what drugs should be avoided and why?

Answer 2

1) Paracetamol, a NSAID, codeine or dihydrocodeine
2) If severe: Morphine or diamorphine
3) Pethidine avoided as accumulation of a neurotoxic metabolites can precipitate seizures. Also short half life

Question 3

How should pain and discomfort associated with acute problems of the oral mucosa be managed?

Answer 3

1) Benzydamine hydrochloride mouthwash or spray

2) Antipyretic action of paracetamol or ibuprofen is often helpful if they also have fever

Question 4

1) Which drug is most effective at managing dental pain?
2) Which drugs should not be used to manage dental pain?
3) Have combination analgesics such as co-codamol shown to be of greater therapy than a single agent?

Answer 4

1) NSAIDs most effective. Paracetamol has analgesic and antipyretic effects but no anti-inflammatory effect
2) Opioid analgesics ineffective in dental pain and their side-effects can be unpleasant
3) Not been shown to provide greater relief of pain than an adequate dose of the non-opioid component given alone. Combination preparations have increased SE

Question 5

Explain how pain following a dental procedure should be managed

Answer 5

1) Take an analgesic before the effect of the local anaesthetic has worn off
2) Postoperative analgesia with ibuprofen or aspirin is continued for about 24 to 72 hours

Question 6

How should pain associated with temporomandibular dysfunction be managed? ( muscles that move the jaw)

Answer 6

1) can be related to anxiety. Muscle spasm may be treated with an overlay appliancewhich provides a free sliding occlusion and may also interfere with grinding
2) Diazepam- muscle relaxant might be helpful

Question 7

outline the management of dysmenorrhoea

Answer 7

1) contraceptive prevents the pain of dysmenorrhoea which is associated with ovulatory cycles
2) Paracetamol or a NSAID will generally provide adequate relief of pain
3) Antiemetic- vomiting associated with endometriosis
4) Antispasmodics (alverine) can be used but does not generally provide significant relief

Question 8

1) why are enteric-coated aspirin tablets unsuitable for single dose analgesic use?
2) Aspirin interacts significantly with a number of other drugs, which interaction is particularly hazardous?

Answer 8

1) Slow onset of action (though their prolonged action may be useful for night pain)
2) Its interaction with warfarin

Question 9

Paracetamol is similar in efficacy to aspirin and is generally preferred especially in elderly. Overdosage with paracetamol is particularly dangerous and is sometimes not apparent for how many day?

Answer 9

hepatic damage sometimes not apparent for 4 to 6 days

Question 10

when might the use of nefopam be considered, and what are the advantages and disadvantages of using this drug?

Answer 10

1) Relief of persistent pain unresponsive to other non-opioid analgesics. causes little or no respiratory depression
2) Sympathomimetic and antimuscarinic side-effects may be troublesome

Question 11

Selective inhibitors of cyclo-oxygenase-2 may be used in preference to non-selective NSAIDs in which patients?

Answer 11

patients at high risk of developing serious gastro-intestinal side-effects

Question 12

why might NSAIDs be useful for treating pain caused by secondary bone tumours?

Answer 12

secondary bone tumours, many of which produce lysis of bone, releasing prostaglandins

Question 13

Compound preparations with low doses of codeine may not provide significant additional pain relief. However a full dose of the opioid (e.g. 60 mg codeine) in compound preparations effectively augments the analgesic activity but side-effects can occur. List some of these side effects

Answer 13

1) Nausea, vomiting, severe constipation, drowsiness, respiratory depression, and risk of dependence
2) Elderly are particularly susceptible. Give lower dose

Question 14

opioids cause dependence and tolerance, but when might regular use of a potent opioid be appropriate?

Answer 14

chronic non-malignant pain and to control pain in terminal illness

Question 15

1) which drug is the most valuable opioid analgesic for severe pain and is the standard against which other opioid analgesics are compared?
2) what side effect does this drug frequently cause?

Answer 15

1) Morphine

2) Frequently causes nausea and vomiting

Question 16

Morphine is the opioid of choice for the oral treatment of severe pain in palliative care. how often are standard and M/R preparations given?

Answer 16

Given regularly every 4 hours (or every 12 or 24 hours as modified-release preparations)

Question 17

Buprenorphine (sch 3 No-Reg) has both opioid agonist and antagonist properties. It has a much longer duration of action than morphine (sublingually 6 - 8 hours). What are the disadvantages of using this drug?

Answer 17

1) may precipitate withdrawal symptoms, including pain, in patients dependent on other opioids
2) abuse potential and may itself cause dependence
3) Effects only partially reversed by naloxone

Question 18

Diamorphine hydrochloride (sch2) (heroin) is a powerful opioid analgesic. Why might this drug be suitable to use in palliative care?

Answer 18

1) greater solubility allows effective doses to be injected in smaller volumes; important in the emaciated patients
2) It may cause less nausea and hypotension than morphine

Question 19

Alfentanil, fentanyl and remifentanil are used by injection for intra-operative analgesia; fentanyl is available in a transdermal patch, how often should this patch be changed?

Answer 19

every 72 hours

Question 20

Methadone is less sedating than morphine and acts for longer periods. Why should it not be administered more often than twice daily?

Answer 20

to avoid the risk of accumulation and opioid overdosage

Question 21

Pethidine produces prompt but short-lasting analgesia; it is less constipating than morphine, but even in high doses is a less potent analgesic. what pain is pethidine used to manage?

Answer 21

used for analgesia in labour (morphine or diamorphine often preferred for obstetric pain)

Question 22

Tapentadol is an opioid-receptor agonist and it also inhibits noradrenaline reuptake. what is the benefit of using this drug?

Answer 22

Nausea, vomiting, and constipation are less likely to occur with tapentadol than with other strong opioid analgesics

Question 23

Tramadol produces analgesia by an opioid effect and an enhancement of serotonergic and adrenergic pathways. what are the advantages and disadvantages of using this drug?

Answer 23

1) Fewer of the typical opioid side-effects e.g. causes less respiratory depression, constipation and addiction
2) But psychiatric reactions have been reported

Question 24

list 3 weak opioid analgesics

Answer 24

1) Codeine: Mild to moderate pain when e.g. paracetamol or ibuprofen have proved ineffective.
2) Dihydrocodeine efficacy similar to codeine. But higher doses may cause more nausea and vomiting.
3) Meptazinol- low repiratory depression. Duration of 2 to 7 hours with onset within 15 minutes.

Question 25

which drugs are commonly used in the management of postoperative pain?

Answer 25

1) Combination of opioid and non-opioid should be used

2) Morphine is used most widely. Tramadol not as effective in severe pain as other opioid analgesics.

Question 26

Intra-operative opioids affect the prescribing of postoperative analgesics. which drugs are not recommended for the management of post operative pain?

Answer 26

1) Buprenorphine may antagonise the analgesic effect of previously administered opioids
2) Pethidine- is metabolised to norpethidine which may accumulate, particularly in renal impairment and cause convulsions