Review of lidocaine plaster prescribing and monitoring in primary care
Authors: Kernaghan M , Kaur G , Stewart J , Pettigrew G 
Published: April 2024

Abstract

Introduction
Lidocaine medicated plasters (LMPs) are accepted by the Scottish Medicines Consortium (SMC) for restricted use in post-herpetic neuralgia where first-line therapies are ineffective or intolerable.[1] Subsequently, LMPs are restricted for use in post-herpetic neuralgia within a large NHS board with Ralvo as formulary brand due to cost-effectiveness. Despite this, the spend on LMPs is increasing with the cost per 1000 list size above the national average.[2]

Aim
To review and improve LMP prescribing and monitoring in a general practice.

Methods
An audit within a GP practice was undertaken by conducting an EMIS search to extract all patients prescribed LMPs within the previous 6 months from December 2022. A baseline audit was completed to determine compliance against the criteria (standards set as 100%), shown in Table 1. Data were analysed using Microsoft Excel. In the interest of improving audit results, a pharmacist then conducted telephone reviews with a view to stopping LMP if appropriate, reducing prescription quantities and/or switching to Ralvo. Post review, criteria were re-audited to determine the impact. Following this, an education session was conducted.

Results
The results against the standards are shown in Table 1.
The LMP reviews resulted in: therapy stopped (n=2; 8%), therapy reduced (n=7; 26%), therapy continued (n=11; 40%), and therapy removed from repeat (n=7; 26%). Reductions were achieved by reducing the number of patches, cutting patches or increasing the patch-free interval. Some patients continued therapy despite off-license indication due to a significant reduction in pain score and benefit in physical function.
Following the audit and review of LMP, an informal general practitioner education session was conducted to promote adherence to formulary and SMC recommendations, aiming to prevent LMP initiation for off-license indications. Impact was not studied.

Conclusion
There is a lack of compliance with SMC and formulary recommendations with all patients in this study being prescribed LMPs for off-licensed indications. Pharmacy involvement in regular reviews could ensure patients are prescribed the most cost-effective brand and ongoing treatment appropriateness assessed, particularly for off-license indications. The study was implemented in one general practice; therefore, there is scope for extrapolation across the National Health Service board with aims to reduce LMP prescription costs and medication burden. Further work is also required to achieve a change in prescribing habits.

References
1. Scottish Medicines Consortium. lidocaine 5% medicated plaster SMC ID 334/06. [online]. Glasgow: Scottish Medicines Consortium (SMC); 2008 [published 2008]. Available from: https://www.scottishmedicines.org.uk/medicines-advice/lidocaine-5-medicated-plaster-versatis-resubmission-33406/
2. Scottish Public Health Observatory Profiles. Lidocaine 5% medicated plaster cost per 1000 list size. Shiny Apps. Glasgow: Public Health Scotland. Available from: https://scotland.shinyapps.io/ScotPHO_profiles_tool/