Analgesia
- Pain is the commonest and most feared symptom associated with cancer
- Chronic pain can be controlled in more than 80% of patients
- WHO analgesia guidelines form the most common template for pain control
- Consists of a three-stepped ladder

- With increasing pain increasing strength of analgesia is required
- On each step of the ladder the maximum dose and frequency should be used
- Drugs should be prescribed on a regular basis not 'as required'
- Co-analgesic agents often have a synergistic effect
- May increase efficacy of a particular analgesic agent
Morphine
- Most commonly used strong analgesic in palliative care
- Should initially be prescribed as an immediate release preparation (e.g. oramorph)
- Can be given as 5-10 mg every four hours
- Dose can be increased every 24 hours until pain is adequately controlled
- Once pain controlled total daily dose can be calculated
- Immediate release can then be substituted for delayed release preparations
- Most commonly used are MST given twice daily or MXL given once daily
- Immediate release preparations can still be given for breakthrough pain
- No ceiling exists for the maximum permissible dose of morphine
- Laxative should be prescribed to prevent constipation
- Patients may also require antiemetic
- Complications include itch, hallucinations, dry mouth
- Respiratory depression is rarely a problem
- Physical dependence may occur
- Psychological dependence and addiction are not a problem in the palliative care setting
- If oral route unavailable consider subcutaneous diamorphine or fentanyl patches
Co-analgesia
- Co-analgesics have little intrinsic analgesic activity
- Have additive effects to analgesic agents
- NSAIDs useful in bone pain
- Anticonvulsants and antidepressants useful in neuropathic pain
- Steroids increase well being
- Benzodiazepines reduce muscle spasm
Other symptoms
Bone pain
- Often well controlled with single fraction of radiotherapy
- NSAID may have useful co-analgesic effect
- Biphosphonates reduce osteoclastic activity and reduce bone pain
Neuropathic pain
- Often resistant to treatment
- Anticonvulsants and antidepressants may have useful effect
- Neurolytic blocks may be considered if fails to respond to pharmacological agents
Liver capsule pain
- NSAID often have excellent additive effect in this situation
- Steroids can reduce swelling, inflammation and pain
- Dexamethasone is usually the drug of choice
Dyspnoea
- Not always due to underlying malignancy
- Consider treatment of any underlying infection, cardiac failure etc.
- Causes of breathlessness related to malignancy include:
- Pleural effusion
- Lymphangitis carcinomatosis
- Intrapulmonary metastases
- Constricting chest wall disease
- Aspiration of a pleural effusion often produces symptomatic improvement
- Pleurodesis with talc or bleomycin only effective drained to dryness
- A pleuro-peritoneal shunt may produce symptomatic improvement
- Steroids produce symptomatic improvement in those with lymphangitis and intrapulmonary metastases
- The respiratory depressant effect of morphine will also reduce dyspnoea
Nausea and vomiting
- Nausea and vomiting is usually multifactorial in origin
- Causes include:
- Hypercalcaemia
- Liver metastases
- Constipation
- Drug side effects
- Intestinal obstruction
- Metaclopramide, domperidone and cyclizine useful if gastric stasis or intestinal obstruction
- 5-HT3 blockers (e.g. ondansetron) useful for chemotherapy induce nausea
- Haloperidol useful in morphine-induced nausea
- Can be administered as a continuous subcutaneous infusion
Constipation
- Treatment should be continuous and anticipatory
- Often a side effect of opiate analgesia
- Can be worsened by inactivity, dehydration and hypercalcaemia
- Opiate-induced constipation best treated with compound preparations
- Contain both a stool softener and stimulant (e.g. co-danthrusate)
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