4.3.2 Other types of pain
Dyskinesia may occur during ‘off’ periods in the end stage of Parkinson’s if the person has been on long term levodopa therapy.
This can be managed with reduction of the levodopa dose but this alone may cause worsening of parkinsonism symptoms and increasing frequency of ‘off’ periods, so a MAO-B or COMT inhibitor may be added if there are no contraindications for their use. If contraindicated, memantine has been helpful in reducing dyskinesia (Varanese et al, 2010).
Neuropathic pain is common in Parkinson’s, indicated by a description of sensory symptoms such as numbness or parathesia and with a burning or radiating pain.
Neuropathic pain is treated with anticonvulsant agents such as gabapentin and pregablin, and anti-depressants such as amitryptiline or duloxetine.
In the dying phase of care the individual will most likely not be able to report pain directly but monitoring the non-verbal indices will guide the family and health professional of the need for analgesia.
Rigidity/stiffness in advanced Parkinson’s may be the result of a variable response to dopaminergic medication, and increased intolerance due to associated neuropsychiatric complications.
Rigidity will usually affect the limbs causing associated pain.
It is difficult at this advanced stage to balance treatment for rigidity without increasing or causing agitation, hallucinations or somnolence.
To lessen rigidity, ensure dopaminergic medication is given on time according to the individual’s usual regimen. In addition to their usual regimen, use doses of dispersible levodopa/benserazide (or rotigotine transdermal patches if their swallow is compromised).
If a percutaneous endoscopic gastrostomy (PEG) is already in situ, this would be used to administer medication. If not in place, administer by nasogastric (NG) tube, which would only be considered as a short term solution.
If a person with Parkinson’s is on an apomorphine pump at the end stage of life it may be appropriate to maintain the infusion to prevent rigidity and pain, but if the person has suffered weight loss or is experiencing side effects, it may be appropriate to lower the rate as guided by the consultant.
In the dying phase of care there may come a time when it is impossible to administer oral medications and transdermal rotigotine patches are contraindicated due to increased agitation or hallucinations. In these circumstances the administration of midazolam in a subcutaneous infusion, under the guidance of the specialist palliative care team, may be effective in treating rigidity.