Pain

 This is commonly treated with an opioid, however if the oral route is unfeasible, the

subcutaneous (S/C) route provides an effective alternative method of administering drugs to patients.

Alternatively, rectal route can be utilised but patients may not favour this due to the need of dosing morphine suppositories every four hours.

 

 Diamorphine is the opioid of choice in most scenarios due to its solubility and can be administered by an infusion device (syringe drivers). However, it is not recommended to start a long acting preparation of opioid in patients close to death or if a fast onset of action is needed. This is due to the delay in the accumulation of the drug required to effective therapeutic levels.

 

 

Dosing:

 Those patients who previously received opioid analgesia should continue through to the final stages and fentanyl patches should be continued in use if prescribed previously. However the conversion ratio should be noted for changing oral or rectal morphine to subcutaneous diamorphine is a 3 to 1 ratio. For example if the patient previously received modifie release of 30mg of oral morphine three times a day with breakthrough doses of 10m immediate release morphine (a total of 90mg daily), this would result in a diamorphine dose of 30mg daily via the subcutaneous route.

 

 If breakthrough pain occurs, a sixth of the daily diamophine dose can be administered subcutaneously. 

Other conditions such as bone pain can be effectively managed by NSAIDs such as an

diclofenac infusion (150mg daily). This is due to the inhibition of prostaglandin synthesis by the COX (cyclooxygenase) enzymes.