This guideline outlines the general management of patients with motor neurone disease (MND) who require pharmacological management of hypersalivation. General Practitioners may be asked to prescribe from this guideline on the advice of an MND specialist. Hypersalivation is often referred to as sialorrhoea or drooling. It affects up to 50% of people with MND and in 42% of these individuals the symptom is poorly controlled. In most cases, saliva problems are the result of poor lip seal and/or impaired ability to swallow, rather than increased saliva production. Patients may complain of excessive, watery saliva or thick, mucousy saliva and it is important to distinguish between the two symptoms as they are both managed differently.
Historically, a range of drugs with antimuscarinic actions have been used in an attempt to control hypersalivation. Blockade of cholinergic muscarinic receptors reduces salivary volume, but a lack of selectivity may result in widespread and undesirable central and peripheral effects, including drowsiness, restlessness, irritability, urinary retention, constipation, and flushing.
There are no randomised controlled comparative studies for the management of hypersalivation in MND, so prescribers should consider evidence for effectiveness, potential side effects and available routes of administration when choosing between them. Of the medicines listed in the following tables only Xeomin® is licensed for chronic sialorrhoea due to neurological disorders: all others are off-label use. It is common practice within treatment of MND patients to use a licensed drug for an unlicensed indication. This is supported by experience in clinical practice.
NICE guidance on MND was published in 2016. For sialorrhoea, this guideline recommends an anticholinergic as first-line treatment and referral to a specialist for botulinum toxin type A where first-line treatment is not effective, not tolerated or is contra-indicated. No specific antimuscarinic is recommended except where the patient has cognitive impairment and glycopyrronium should be used first-line as it has fewer central nervous system side effects.