4.11 Drugs for dementia

ChoiceDrugDosage
1st choice cholinesterase inhibitorDonepezil tablets 5mg, 10mg; orodispersible tablets 5mg, 10mgDose:
Initially 5mg once daily at bedtime*, increased if necessary after one month to 10mg daily

*If sleep disturbances are noted, the time of dosing may be chosen based on individual tolerability
2nd choices cholinesterase inhibitors

Galantamine m/r capsules 8mg, 16mg, 24mg

Gatalin XL® is the recommended cost-effective choice (prescribe by brand)

Dose:
Initially 8mg once daily for 4 weeks increased to 16mg once daily for 4 weeks; maintenance 16-24mg once daily
Or
Rivastigmine capsules 1.5mg, 3mg, 4.5mg, 6mg; patch 4.6mg/24 hours and 9.5mg/24 hoursDose:
Orally: initially 1.5 mg twice daily, increased in steps of 1.5 mg twice daily at intervals of at least 2 weeks according to response and tolerance; usual range 3–6 mg twice daily; max. 6 mg twice daily; if treatment interrupted for more than several days, treatment should be retitrated from 1.5 mg twice daily

Transdermal: initially 4.6mg/24 hours after a min of 4 weeks and if well tolerated the dose should be increased to 9.5mg/24 hours

(see BNF for full details)
In line with NICE guidanceMemantine tablets 10mg, 20mg; treatment initiation pack 7x5mg, 7x10mg, 7x15mg and 7x20mg; oral drops 5mg/actuationDose:
Initially 5mg once daily, increased in steps of 5mg at weekly intervals; usual maintenance 20mg daily; max 20mg daily

Prescribing Notes

  • See COMPASS therapeutic notes on the management of dementia.
  • See NICE NG97 Dementia: assessment, management and support for people living with dementia and their carers, June 2018 and BMJ visual summary.
  • For people who are not taking an AChE inhibitor or memantine, prescribers should only start treatment with these on the advice of a clinician who has the necessary knowledge and skills. This could include:
    • secondary care medical specialists such as psychiatrists, geriatricians and neurologists
    • other healthcare professionals (such as GPs, nurse consultants and advanced nurse practitioners), if they have specialist expertise in diagnosing and treating Alzheimer’s disease.
  • Some commonly prescribed medicines are associated with increased anticholinergic burden and therefore cognitive impairment. Various tools have been devised to assess anticholinergic burden and aid medication reviews, e.g. Anticholinergic Cognitive Burden (ACB) Scale.
  • Before starting treatment with an AChE Inhibitor check if the patient is taking a bladder anticholinergic. Co-prescribing is not recommended, see Urinary Incontinence (UI) in Dementia article, Medicines Management Newsletter February 2020.
  • Once a decision has been made to start an AChE inhibitor or memantine the first prescription may be made in primary care.
  • Serious skin reactions have been reported in patients receiving galantamine. Patients should be informed about the signs of serious skin reactions and that galantamine should be discontinued at first appearance of rash.
  • Offer co-prescription of AChE inhibitor and memantine for severe Alzheimer’s disease and consider co-prescription in moderate disease.
  • For people with an established diagnosis of Alzheimer’s disease primary care prescribers may start memantine without taking advice from a specialist clinician.
  • Starting doses of AChE inhibitors are not therapeutic doses and should be increased as per titration schedule.The dosing schedules in the table above are suggested dosing schedules only.
  • Do not stop AChE inhibitors because of disease severity alone. However, in patients progressing to very advanced dementia (end of life care), review the overall benefit of these agents and consider discontinuation.
  • In patients progressing to very advanced dementia (end of life care), assess the overall benefit of these agents and consider discontinuation.
  • If nausea develops after initiation of an AChE inhibitor, reduce the dose and titrate up more slowly.
  • Donepezil orodispersible tablets are available for patients who have difficulty in swallowing solid oral dose formulations.
  • Rivastigmine patches may be an appropriate choice of formulation where a trial of oral medicine was poorly tolerated (see BNF notes on switching from oral to transdermal therapy).
  • Be aware of the potential for confusion in dosage units with memantine oral solution. Ensure that dose instructions specify the number of milligrams and the corresponding number of pumps required. The person administering memantine oral solution should be counselled on how to administer the required dose. Refer to Medicines Safety Matters Newsletter – Nov 2014.