SP7 Switching to clonidine transdermal patches in four paediatric cases: strategies benefits and challenges

Background Clonidine is an alpha-2 agonist acting in the central nervous system (CNS) and licensed for use in all grades of hypertension, prophylactic management of migraine or recurrent vascular headache and management of vasomotor conditions.1 In paediatrics, clonidine has been used for a variety of indications which include use as pre-medication, as analgesia adjuvant, for sedation in paediatric intensive care units (PICU), treatment of spasticity and dystonias, prevention of emergency agitation and in hypertension.2 Oral clonidine has a short half-life of 12 to 16 hours and is associated with peaks and troughs in drug concentration resulting in 2 to 8 hourly dosing intervals. Long-term intravenous clonidine is unviable for a variety of reasons which includes intravenous (IV) access, infection risks and complex ongoing management. Clonidine transdermal patches, approved for use in 1984, provide approximately constant therapeutic drug level for 7 days3 and may represent a viable option for paediatric patients on long-term clonidine. Aim To describe the strategies adopted in converting four paediatric patients to clonidine transdermal patches from either enteral or parenteral clonidine; the benefits and challenges of the conversion. Method The intrinsic characteristics of clonidine transdermal patches4 and the therapeutic/clinical goal for each patient informed the switch strategy. Evaluation of the effect of switch was done at least three months after switch through consented open interviews with stakeholders, and evaluation of clinical symptoms. Results The switch strategy to clonidine patch is complex and different for each patient. The factors to consider include: (i) clinical/therapeutic goal for the patient; (ii) the characteristics of the patch (iii) patient’s characteristics – weight and surface area; (iv) detailed counselling of patients and carers; (v) individualised prescription; (vi) ongoing review of supply and patch effectiveness. All patients were switched to patches and achieved approximately equivalent clinical effects, although one child required further dose adjustment. One parent considered the switch to patches to be very good: ‘We struggled....we employed the services of night carers four times a week...and we were too exhausted. (The change) has a massive impact on everyone’s quality of life...it has been brilliant’. Another parent observed that the application of patches was not difficult and that the change has been good: ‘The nurse gives me the patch, I label them and make three lines on the child’s skin and rotate the patch, so there is always a space spare for 2 weeks before re-applying there again. It is not difficult’. In a clinic letter for another child who was switched to patches, the clinician noted: ‘Since he changed to the patches there was no change in his dystonia (and) he has tolerated well. According to mother the main trigger for his dystonic episodes is heat’. One of the nurses looking after another child considered the switch overall to be poor to fair: ‘(Using patches) is good in general as they (children) are not attached to pump and easy to move them around...(however) for him (this child), he was too sweaty and patch will fall off...his skin is really dry/red around the cover patches. It would be better if you didn’t have as many as nine patches to apply. It is difficult to wash him with so many patches. He responded better with IV clonidine but we were able to get him off infusion to patches. Education on what to do when it (the patch) falls off will be really useful’. Conclusion The use of clonidine transdermal patches is a viable option for children needing long-term clonidine. This option has the potential to offer significant cost saving to the National Health Service (NHS) and improved quality of life of children and their carers; especially in those cared for at home. The strategy for conversion is complex and requires taking a number of factors into account. Switch to transdermal patches will not be suitable for all patients and criteria for selecting suitable patients and a generalised framework for switching are yet to be fully described. References SPC. Clonidine 25 mg tablets BP. Summary of Product Charcteristics 2015. Retrieved June 27, 2019, from Electronic Medicines Compendium: https://www.medicines.org.uk Basker S, Singh G, Jacob R. Clonidine in paediatrics - a review. Indian J Anaesth 2009;53:270–80. SPC. Catapres-TTS. Summary of Product Charcteristics 2016. Retrieved June 27, 2019, from https://docs.boehringer-ingelheim.com/Prescribing%20Information/PIs/Catapres%20TTS/CatapresTTS.pdf Sica DA, Grubbs R. Transdermal clonidine: therapeutic considerations. The Journal of Clinical Hypertension 2005;7:558–562.