• Consider a stepped approach to the management of constipation due to colonic dysmotility in Parkinson's disease:
• Increase dietary fibre and fluid intake (advise at least eight glasses of water per day).
• Increase exercise.
• Use fibre supplements (such as ispaghula husk).
• Use a stool softener (such as docusate).
• Use an osmotic laxative, such as lactulose or macrogols (Movicol^® or Laxido^®).
• Enemas may occasionally be required.
• See the CKS topic on Constipation.

In depth

• Advise people who have sudden onset of sleep without awareness or warning signs not to drive and to consider any occupational hazards.
• Initial management of daytime hypersomnolence depends on its likely cause:
• Anti-parkinsonian medication (such as dopamine agonists):
• Seek specialist advice.
• Sedating medication (such as antihistamines, antipsychotics, and some antidepressants):
• Reduce, stop, or use an alternative medication; seek specialist advice if necessary.
• Inadequate rest at night:
• See Sleep disturbance.
• Dementia.
• Consider requesting advice from, or an interim referral to, the person's Parkinson's disease specialist team, so that:
• Medication that could be causing or contributing to daytime hypersomnolence can be reduced or stopped.
• Modafinil can be considered for daytime hypersomnolence (off-licence use). However:
• Modafinil is contraindicated in people with uncontrolled moderate to severe hypertension, and in people with arrhythmias.
• Modafinil is associated with skin and subcutaneous tissue reactions, and with the development of neuropsychiatric disorders.

In depth

• Treat any condition that may be causing or exacerbating cognitive impairment, such as depression or acute infection.
• Consider safely reducing or discontinuing (on specialist advice if necessary) any drugs that may be causing or exacerbating cognitive impairment, including:
• Drugs with an antimuscarinic action, including tricyclic antidepressants, tolterodine, and oxybutynin.
• H₂-receptor antagonists such as ranitidine.
• Benzodiazepines.
• Amantadine.
• Dopamine agonists.
• Refer for specialist assessment for:
• Optimization of anti-parkinsonian drug regimen, and/or
• Use of a cholinesterase inhibitor. Currently, only rivastigmine is licensed for use in people with Parkinson's disease dementia in the UK.

In depth

• Consider referral to a speech and language therapist for:
• Full assessment of swallowing ability.
• Advice, and a trial of behavioural management techniques to encourage regular saliva swallows.
• Use of a portable metronomic brooch as a reminder for saliva swallows.
• Lip-seal and swallow exercises.
• Consider referral to the person's Parkinson's disease specialist team.

In depth

• Severe sweating may occur as an end-of-dose 'off' phenomenon. It may also occur during the 'on' motor state, when it is usually associated with dyskinesia.
• Exclude other causes of excessive sweating. See the section on Initial assessment in the CKS topic on Hyperhidrosis.
• Consider referral to the person's Parkinson's disease specialist team for a review of medication — sweating may respond to adjustments in anti-parkinsonian treatment.

In depth

• If falls occur soon after the onset of parkinsonism, suspect an alternative diagnosis, such as progressive supranuclear palsy.
• Refer to the person's Parkinson's disease specialist for review of the diagnosis.
• Assess and treat Postural (orthostatic) hypotension.
• Consider referral for multifactorial and multidisciplinary assessment and interventions to prevent falls.
• This is likely to be delivered by a specialist falls service and, ideally, will include a professional with understanding of Parkinson's disease.
• For more information, see the CKS topic on Falls - risk assessment.

In depth

• Refer promptly to a speech and language therapist for:
• Assessment and swallowing advice.
• Further investigations such as videofluoroscopy or fibre-optic endoscopic examination of swallow safety (particularly if silent aspiration is suspected).
• Liaison with the person's Parkinson's disease specialist team is also recommended as symptoms may respond to alterations to anti-parkinsonian medication.

In depth

• If an impulse control disorder (such as hypersexuality, pathological gambling, or compulsive buying) or dopamine dysregulation syndrome is suspected, contact the person's Parkinson's disease specialist team.
• Explanation may be beneficial, and non-pharmaceutical measures, such as restriction of spending and internet access (for example to gambling sites), could be advised.

In depth

For nausea or vomiting after starting or increasing the dose of a dopaminergic drug

• Initially, if nausea is mild:
• Reassure that nausea often settles over time as tolerance occurs.
• Advise the person to take their medication with food.
• If nausea persists or is more severe:
• Prescribe domperidone, reducing or stopping it when the nausea or vomiting settles.
• Do not use metoclopramide or prochlorperazine.
• Consider seeking the advice of a specialist, who may recommend one or more of the following:
• An increase in the proportion of decarboxylase inhibitor to levodopa (only feasible for co-careldopa).
• A slower titration of the anti-parkinsonian drug.
• A switch to an alternative.

For nausea or vomiting unrelated to medication

• If an anti-emetic is required, use domperidone, reducing or stopping it when the nausea settles. Avoid metoclopramide or prochlorperazine.

In depth

• Liaise with, or refer to, the person's Parkinson's disease specialist team for the following types of pain, as they may require an alteration to anti-parkinsonian medication:
• Dystonic pain.
• Primary or central neuropathic pain.
• Akathisia-related pain.
• The following types of pain can initially be managed in primary care, but liaise with, or refer to, the person's Parkinson's disease specialist team if pain cannot be controlled with these measures:
• Musculoskeletal pain:
• Treat with simple analgesics and regular exercise; consider physiotherapy.
• If appropriate, see the CKS topics on Shoulder pain and Back pain - low (without radiculopathy).
• Radicular neuropathic pain:
• Treat with simple analgesics, drugs specifically for neuropathic pain such as gabapentin, and gentle exercise.
• If appropriate, see the CKS topics on Neck pain - cervical radiculopathy, Neuropathic pain - drug treatment and Sciatica (lumbar radiculopathy).

In depth

• Consider a stepped approach to the management of postural (orthostatic) hypotension in Parkinson's disease:
• Stop or reduce the dose of antihypertensive medications.
• Reduce or change anti-parkinsonian drugs after discussion with specialist services.
• Advise the person to increase their dietary salt and fluid intake, to avoid caffeine at night, to eat frequent, small meals, and to avoid alcohol.
• Advise the person to elevate the head of their bed by 30–40 degrees.
• Consider prescribing compression stockings after excluding arterial insufficiency (see the CKS topic on Compression stockings).
• Consider referring people with persistent or troublesome symptoms to a unit with expertise in falls and syncope.
• A salt-retaining steroid (such as fludrocortisone) may be recommended.
• Occasionally, midodrine (a direct-acting sympathomimetic) may be prescribed, but this is only available on a named-patient basis.

In depth

• Have a low threshold for suspecting psychotic symptoms in people with Parkinson's disease.
• Consider excluding causes besides Parkinson's disease itself, anti-parkinsonian drugs, and dementia, including:
• Delirium caused by other physical illness or drug treatments.
• Other comorbid mental illness, such as depression.
• Liaise with, and promptly refer to, specialist services all people with Parkinson's disease who develop psychotic symptoms:
• Mild psychotic symptoms may not need to be actively treated if they are well tolerated by the person and carer.
• More severe psychotic symptoms may require gradual withdrawal of precipitating anti-parkinsonian medication or the use of an atypical antipsychotic (such as clozapine, under the care of a mental health specialist).

In depth

• If hypersexuality is reported:
• Suspect that it may be caused by dopaminergic therapy (even when there is erectile dysfunction) and contact the person's Parkinson's disease specialist team.
• If erectile dysfunction or anorgasmia is reported:
• Exclude comorbid endocrine abnormalities (such as hypothyroidism or hyperprolactinaemia).
• Consider the possibility of underlying depression.
• Consider discontinuing drugs associated with erectile dysfunction (such as alpha-blockers) or anorgasmia (such as selective serotonin reuptake inhibitors [SSRIs]).
• Consider prescribing a phosphodiesterase type-5 inhibitor for erectile dysfunction (sildenafil, tadalafil, or vardenafil), which are available on the NHS for men with Parkinson's disease. The prescription must be endorsed 'SLS' by the prescriber.
• Avoid these drugs in people with hypotension (systolic blood pressure less than 90 mmHg), and use with caution in people with postural (orthostatic) hypotension.
• For more information, see the CKS topic on Erectile dysfunction.
• Consider referral to a urological specialist or specialist services for erectile dysfunction.

In depth

• Take a full sleep history and advise good sleep hygiene.
• Identify whether any of the following may be present and manage them appropriately, usually by requesting an interim referral or advice from the person's Parkinson's disease specialist team:
• Conditions related to Parkinson's disease:
• Restless legs syndrome.
• Periodic leg movements of sleep.
• Rapid eye movement (REM) sleep behaviour disorder.
• Nocturnal akinesia (inability to turn over in bed).
• Nocturia (see Urinary dysfunction).
• Conditions that may be caused by anti-parkinsonian medication (such as selegiline and dopamine agonists):
• Vivid dreams or nightmares.
• Hallucinations.
• See the CKS topic on Insomnia.

In depth

• If the person presents with an abrupt change in voiding pattern, exclude urinary tract infection.
• If frequency or polyuria are present, consider testing for diabetes.
• Consider discussing the use of an antimuscarinic drug (such oxybutynin or tolterodine) with the person's Parkinson's disease specialist team:
• Such treatment can induce a toxic confusional state and may worsen symptoms of dementia.
• Drugs that do not cross the blood–brain barrier (such as trospium chloride) may be less likely to induce confusion.
• Consider referral to a urological specialist if there are refractory or persistent bladder problems.

In depth

• Although unintended weight loss occurs in over 50% of people with Parkinson's disease, other medical causes for weight loss (such as malignancy and endocrine diseases) should also be considered.
• If other medical causes of weight loss can be safely excluded, consider:
• Liaising with the person's Parkinson's disease specialist team to arrange:
• Investigations of swallowing — see Impaired swallowing (dysphagia).
• Review of anti-parkinsonian medications, as weight loss appears to correlate with severity of dyskinesia.
• Referring to a dietitian, and the provision of dietary supplements on the advice of the dietitian.

In depth