Parkinson’s disease

Antiparkinsonian medicines are essential medicines for treating the motor complications of Parkinson’s disease (PD). For most people with PD, medication is the only way to control their symptoms. The correct medication must be given on time and should not be stopped suddenly as this may result in severe complications such as:²¹⁸

• Unable to swallow (increasing the risk of aspiration)
• Unable to speak and/or move (increasing their dependence on others)
• Acute akinesia (feeling frozen and stiff and being unable to move one’s muscles)
• Neuroleptic malignant syndrome (a life-threatening complication characterised by hyperthermia)

Care must be taken when absorption may be impaired, for example in gastroenteritis or surgery and in people who become nil by mouth.

During admission to hospital, care homes or during other transitions of care, poor management of antiparkinsonian medications can lead to poor outcomes for individuals. These may continue following discharge. Everyone administering antiparkinsonian medication should be aware of the importance of dosage timing.²¹⁹

Most people with PD will be managed by a specialist in movement disorders and/or a multidisciplinary team, including a Parkinson's disease nurse specialist, physiotherapist and occupational therapist, who can advise on the management of both motor and non-motor symptoms and complications, to support improvements in activities of daily living.

Management should be individualised based on the person's symptoms and wishes, comorbidities, other medications and potential benefits and harms of the different drug classes. It should be aimed at reducing movement dysfunction, tremor and postural instability, while managing cognitive changes and minimising side effects.

For early, symptomatic PD, the first-choice options include:²²⁰

• levodopa
• a non-ergot dopamine agonist such as pramipexole, ropinirole or rotigotine patch
• a monoamine oxidase type B (MAO-B) inhibitor such as selegiline or rasagiline

The choice of therapy depends on multiple factors such as individual preference and the expected risks and benefits of the medications in that individual. Medication should be initiated and followed up by a specialist.

If the individual has developed dyskinesia (involuntary movements) and/or motor fluctuations, including medicines 'wearing off', consult a PD specialist to consider modifying the individual’s therapy.²²⁰ Adjuvant treatment available includes catechol-O-methyl transferase (COMT) inhibitors (such as entacapone or opicapone) and amantadine.

Liaise with the PD specialist if changes to antiparkinsonian medication are needed.

• Only start or alter antiparkinsonian medication on the advice of the PD specialist
• Titrate drug treatment according to recommendations made by the PD specialist
• Do not suddenly stop any antiparkinsonian medication, as this can precipitate acute akinesia or neuroleptic malignant syndrome
• Specify times of medication administration
• Ensure that changes to repeat medications are made accurately and promptly

Factors that aid or impair adherence in this area and how to address them

• Co-careldopa and co-beneldopa are available in various strengths and formulations which facilitate adaptation of regimes to enable optimal control. For example, dispersible co-beneldopa may be a useful product where swallow is difficult in the morning or rapid onset of action is required.²²¹
• Caution should be exercised in the use of a liquid formulation where swallowing thin liquids is provoking cough, and recommendations have been made to avoid thin fluids. In this situation, a crushed tablet given in yoghurt may be a safer and more effective way to administer. Note, crushing tablets may change their licensing status to “off-label”.
• Transdermal formulations may be a useful option if there are swallowing difficulties present. However, specialist input is required to advise on suitable doses to use; refer to local guidance.

These medicines must not be stopped suddenly as this may lead to acute akinesia or neuroleptic malignant syndrome. Care must be taken when absorption may be impaired, for example in gastroenteritis or surgery and in people who become nil by mouth.

A key issue with antiparkinsonian medication is timing:²²²

• Medication should be taken at specific times to ensure that the control of symptoms is maintained without deterioration. Delay of medication can result in someone being unable to function independently at work or at home, and becoming reliant on others for simple everyday activities such as walking and eating
• It is crucial not to stop, omit or delay PD medications for any significant length of time (more than 30 minutes)²¹⁸ as this may cause significant exacerbation of symptoms and distress
• In extreme cases, missed doses may lead to the potentially fatal neuroleptic malignant syndrome (NMS)

If the individual cannot remember to take their medication on time, consider exploring adherence issues and strategies to help remember medication. These could include aids such as pill timers, apps, alarms and dosette boxes.

Individuals may receive support from carers around medication. Everyone involved in the care of someone with PD should be aware of the importance of the timing of medications and strategies should be in place supporting this.

If a person with PD is admitted to hospital, a care home, or respite care, ensure that staff are aware of the risks of sudden changes in antiparkinsonian medication and the importance of adhering to prescribed dosage and timing of medications.

People with PD who are admitted to hospital or care homes should have their medicines:

• given at the appropriate times, which in some cases may mean allowing self-medication
• adjusted by, or adjusted only after discussion with, a specialist in the management of Parkinson's disease

Parkinson’s UK have a range of tools, resources and learning to support healthcare professionals to deliver time critical medication to people with Parkinson's as part of their Get It On Time campaign.

If the individual is unable to swallow the medication, consider suggestions such as medication review (of other non-antiparkinsonian medication), different-shaped tablets/capsules and soluble formulations. Ensure input from Speech and Language Therapy (SALT) to complete a full swallowing assessment and recommend strategies.

Explore any other difficulties in taking their current medication. Consider dexterity issues and the ability to open packaging, exploring alternatives where appropriate.

Impulse control disorders

Impulse control disorders (compulsive gambling, hypersexuality, binge eating or obsessive shopping) can develop in a person with PD who is on any dopaminergic therapy at any stage in the disease course. This applies particularly to those with a history of impulsive behaviours, alcohol consumption or smoking. Individuals should be informed about the different types of impulse control disorders. Although particularly noted with the dopamine agonist class of medications, this side effect can occur with any dopaminergic therapy.

It is essential that the specialist PD team are informed if these symptoms are detected, so they can advise on medication alteration for the individual.

Medicines to avoid

Some medications are contra-indicated in individuals with PD, care should be taken to review individual drug information when prescribing new medications.

Contra-indicated medications include (not exhaustive):

• haloperidol
• metoclopramide
• prochlorperazine
• chlorpromazine
• fluphenazine
• perphenazine
• trifluoperazine
• flupentixol

Do not suddenly stop any antiparkinsonian medication, as this can precipitate acute akinesia or neuroleptic malignant syndrome.

Specific areas/situations where medication may need to be introduced or increased

• constipation, nausea and vomiting
• pain
• sleep disturbance and daytime sleepiness
• depression and anxiety
• dementia and cognitive impairment
• impulse control disorders and psychotic symptoms
• orthostatic hypotension
• speech and swallowing problems and weight loss
• excessive salivation and sweating
• bladder and sexual problems

Individuals should be asked about non-motor symptoms which might be impacting on their quality of life. Parkinson’s UK’s website has information on these symptoms. There is a downloadable non-motor symptoms questionnaire completed by the person and/or their family/carers, which may help assess symptoms.

Most people with PD will be managed by a specialist in movement disorders and/or a multidisciplinary team, including a PD nurse specialist, who can advise on the management of non-motor symptoms and complications. However, primary healthcare professionals may have a role to play in the management of some of these issues, depending on local guidelines and expertise.

Constipation:

• Consider a stepped approach to the management of constipation in PD
• Refer to Parkinson's UK booklet Looking after your bladder and bowels when you have Parkinson's
• See constipation hot topic for more information and treatment options
• If constipation persists, liaise with the PD specialist team, as alteration of antiparkinsonian medication may be helpful

Nausea and vomiting:

Mild nausea or vomiting can be associated with starting or increasing the dose of levodopa or a dopamine agonist:

• Initially, if nausea or vomiting is mild and related to starting or increasing the dose of levodopa or a dopamine agonist: 
  • Reassure the individual that nausea often settles over time as tolerance to adverse effects builds up
  • Advise to take their medication with food
• If nausea or vomiting persists, is severe, or is unrelated to levodopa or dopamine agonist drug treatment, seek specialist advice:
  • Do not use metoclopramide or prochlorperazine anti-emetics — these can cause or exacerbate parkinsonism

Pain:

• Offer management for the following types of pain in primary care: 
  • Musculoskeletal pain
  • Radicular neuropathic pain (shooting pain)
  • The Parkinson's UK website has information about pain in Parkinson's and covers the management of multiple common types of pain in PD
• Seek specialist advice or arrange a specialist review if pain remains uncontrolled
• Liaise with, or arrange a review with, the PD specialist team for the following types of pain,as they may require an alteration to antiparkinsonian medication: 
  • Dystonic pain. See the Parkinson's UK website for information about muscle cramps and dystonia
  • Primary or central neuropathic pain
  • Akathisia-related pain

Does the person understand the outcomes of the review, including risk and benefits?

• All people affected by PD should be involved in deciding their treatment and care. Choice of treatment should suit the patient's needs and preferences, considering potential side effects and advantages.

Is drug therapy tailored to the individual?

The main aims of drug treatment are to:

• maximise function
• control symptoms
• keep the medication regime as simple as possible
• aid adherence
• reduce the likelihood of side effects as far as possible

Agree the plan

• It is important that lifestyle, amount of support at home and individual preferences are all taken into consideration
• Any medication changes should be shared and agreed with the individual (as a written and/or verbal plan), especially as dose timing is important
• Offer non-pharmacological approaches for the management of non-motor symptoms, e.g. dietary modifications for constipation

• self-management/support tools
• clinician decision aids

Non-motor symptoms of Parkinson's - information on Parkinson's UK website

Parkinson's non-motor symptoms questionnaire