Rivastigmine (Exelon) transdermal patch: risk of medication errors

Medication errors and inappropriate use of the rivastigmine transdermal patch have been reported, some of which resulted in overdose. Healthcare professionals should be aware of the correct use of rivastigmine, and should advise patients and caregivers as outlined in this article.

Rivastigmine (Exelon) transdermal patch is indicated for the symptomatic treatment of mild to moderately severe Alzheimer’s dementia. The patch is available in two doses: 4.6 mg/24 hours; and 9.5 mg/24 hours. Treatment is started with one 4.6 mg/24 hour patch. After a minimum of 4 weeks and if tolerated well, the daily dose should be increased to the recommended effective dose of 9.5 mg/24 hours.

Risk of medication errors and inappropriate use

Case reports of medication errors and inappropriate use of the rivastigmine transdermal patch have been reported, some of which resulted in overdose and required admission to hospital. The most frequently reported causes were lack of patch removal and application of more than one patch at the same time. Other causes were: application of the patch to non-recommended sites; patch application to the same area for several weeks; cutting the patch into several pieces; and dose errors in prescribing or dispensing.

This article aims to remind healthcare professionals about the correct use and administration of rivastigmine transdermal patches as outlined in the Summary of Product Characteristics. Health professionals should also advise patients and caregivers before starting treatment; similar to any treatment initiated in patients with dementia, rivastigmine should only be started if a caregiver is able to regularly give and monitor treatment. Further information for patients can be found in the Exelon transdermal patch Patient Information Leaflet.

Advice for healthcare professionals:

  • symptoms of rivastigmine overdose include nausea, vomiting, diarrhoea, hypertension, and hallucinations; bradycardia and/or syncope, associated with malaise or falls, may also occur

  • in case of suspected overdose, all rivastigmine patches should be removed immediately and no further patch should be applied for the next 24 hours
  • it is important to instruct patients and caregivers on the proper use of the transdermal patch, particularly that:

    • only one patch should be applied per day to healthy skin on the upper or lower back, upper arm, or chest
    • the patch should be replaced by a new one after 24 hours, and the previous day’s patch must be removed before application of a new patch to a different skin location
    • aplication to the same skin location within 14 days should be avoided to minimise skin irritation
    • the patch should not be cut into pieces

A letter has been sent to healthcare professionals in April 2010 with information on this risk (251Kb).

Reporting of suspected adverse reactions

Please report suspected adverse reactions associated with the use of the rivastigmine patch to us on a Yellow Card. Patients and caregivers can also report any suspected reactions to us via the Yellow Card Scheme.
 

Article citation: Drug Safety Update June 2010, vol 3 issue 11: 2.

Published 11 December 2014