Analgesia guidelines for acute pain management in adults

Paracetamol 1g orally or IV 4-6 hourly regularly or as needed (maximum 4g in 24 hours)

• do not prescribe this in conjunction with codydramol or other paracetamol-containing compound preparations
• due to the considerably greater costs, paracetamol IV should be reserved for those patients unable to take by oral route
• review IV route after 24 hours

Ibuprofen 600mg orally three times a day (maximum 2400mg in 24 hours)

or

Diclofenac 100mg rectally every 18 hours (maximum 150mg in 24 hours)

• this should be reserved for patients with no oral intake
• NSAIDs should be prescribed on a regular (not as needed) basis for maximum benefit - review the prescription after 3 days
• the combination of an NSAID and low dose aspirin may increase risk of developing GI side effects, so this combination should only be used when necessary and with close monitoring
• the diclofenac 75mg IM preparation should not be used (associated with persistent injection site pain, muscle necrosis and abscess formation)

Contra-indications to NSAIDs

• active or recurrent GI bleeding/ulceration whether or not in relation to previous NSAID therapy (see separate parecoxib/etoricoxib guidelines)
• severe heart failure for ibuprofen, mild to severe heart failure for diclofenac
• cerebrovascular disease for diclofenac
• peripheral arterial disease and ischaemic heart disease for diclofenac

Cautions

• history of adverse drug reaction to aspirin or other NSAIDs
• cardiac impairment/failure (both ibuprofen and diclofenac)
• NSAIDs may impair renal function (care in those at increased risk - elderly, postoperative patients, hypovolaemia, septicaemia, dehydration)
• left ventricular dysfunction (for diclofenac)
• oedema for diclofenac
• coagulation defects
• connective tissue disorders
• Crohn’s disease & ulcerative colitis
• hypertension for diclofenac
• uncontrolled hypertension for ibuprofen
• cerebrovascular disease for ibuprofen
• ischaemic heart disease & peripheral arterial disease for ibuprofen
• asthma

Codydramol 2 tabs 4-6 hourly as needed (maximum 8 tabs in 24 hours)

• codydramol 10/500 contains dihydrocodeine 10mg and paracetamol 500mg
• this may be prescribed on a regular basis for mild pain if paracetamol on its own is insufficient and when NSAIDs or COX II inhibitors cannot be used

Use a combination of:

1. paracetamol (regular - as advised for mild pain) and
2. NSAID or COX II Inhibitor (regular - as advised for mild pain) and
3. dihydrocodeine or tramadol (moderate strength opiate)

• tramadol is a more potent analgesic than dihydrocodeine
• 10% of the caucasian population experience no pain relief from dihydrocodeine due to a lack of the relevant enzyme to convert the prodrug to its active form
• although tramadol may have some benefits over dihydrocodeine, there are some specific potential problems with tramadol and these need to be carefully considered especially in the elderly (see below)

Dihydrocodeine 30mg 4-6 hourly as needed or regularly(maximum 240mg in 24hours)

or

Tramadol 50-100mg 4-6 hourly as needed or regularly (PO, IV or IM routes, maximum 400mg in 24hours)

• avoid using 60mg dihydrocodeine dose as confers little additional analgesic benefit over the 30mg dosage and increases likelihood of constipation and other side effects
• tramadol is associated with fewer typical opioid side effects leading to less respiratory depression, sedation and constipation. The incidence of nausea and vomiting is thought to be similar compared to equi-analgesic doses of other opioids. Some patients may be susceptible to unpleasant psychogenic reactions eg. agitation, hallucinations, dysphoria.
• reduce dose or avoid using in elderly or debilitated patients due to potentially increased risk of confusion or hallucinations in these patients
• avoid using tramadol if history of epilepsy, acute head injury, impaired conscious level because the risk of having seizures may be increased in these patients
• reduce dose or avoid using in renal impairment (tramadol is renally excreted)
• not suitable as replacement for conventional opioids in opioid-dependent patients due to its effects on other receptor targets besides mu opioid receptors
• avoid using in pregnancy and breast-feeding
• caution advised if used in conjunction with tricyclic antidepressants or SSRIs (risk of serotonin syndrome). Do not give in combination with an MAOI antidepressant
• prescribe a laxative with all opioid prescriptions, including moderate strength opioids

Use combination of

1. paracetamol (regular - as advised for mild pain) and
2. NSAID or COX II Inhibitor (regular - as advised for mild painee above) and
3. morphine by the appropriate route of administration:

• morphine PO - 0.3mg/kg 4 hourly initially (as oral morphine solution.)
• once total 24 hour opioid requirements are known, convert 24 hour short-duration oral morphine solution dose to long-acting morphine MR or Zomorph (split into 2 doses, 12 hours apart)
• morphine IV - 1mg/min for 5 minutes, then 1mg every 5 minutes until comfortable
• morphine IM or SC - 0.1-0.2mg/kg 2 hourly as needed (lower dose for elderly or frail patients)
• morphine PCA - contact Acute Pain Team (recovery room) or duty anaesthetist

Alwaysprescribe a laxative with opioid prescriptions eg lactulose 15ml twice a day or senna 7.5mg or 15mg every night.  

If being discharged home on newly prescribed strong opioids advice to be obtained from Acute Pain Service for opioid dose reduction and discontinuation. APS will provide a completed proforma detailing instructions for primary care.

• refer to separate guideline for PONV management
• antiemetics should always accompany an opioid prescription

Cyclizine 50mg IM or IV 8 hourly as needed

and

Prochlorperazine 12.5 mg IM or PO 8 hourly as needed

2nd line Ondansetron 4mg IM or IV or PO 8 hourly as needed