Transdermal Patches: Errors That Stick

The transdermal patch is a unique drug delivery system with its own unique risk of errors. The Institute for Safe Medication Practices (ISMP) analyzed four years of voluntary reports submitted to the ISMP Medication Error Reporting Program (MERP) which uncovered common themes of transdermal patch errors. 

There were over 50 reports analyzed and the following were most common among the reports: 

• errors in the frequency of patch application or removal;
• lack of awareness of patches on patient’s skin;
• dose confusion due to labeling;
• inappropriate patch prescribing;
• wrong dose dispensing errors;
• patch cover applied without medication patch; and 
• wrong medication dispensed due to similar ingredients.

There were ten reports associated with an error in the frequency of patch application. These reports were often cases in which estradiol patches—which depending on the brand—will be applied once or twice a week. The result of these errors included both overdoses (patches applied twice a week) and underdoses (patches applied once a week). In one error, the contraceptive patch Xulane was confused by a prescriber who then ordered the hormone replacement, CombiPatch, because they only searched by the word “patch.” 

There was an interesting error where “TTS-2” was interpreted to mean Tuesday, Thursday, and Saturday, and the person did not know that “TTS-2” was the nomenclature used for the 0.2 mg/24 hour CATAPRES-TTS-2 (transdermal therapeutic system) brand of cloNIDine patches. This treatment should only be applied weekly. 

Additional errors include the confusing dose labeling of scopolamine patches, inappropriate prescribing of fentaNYL patches, practitioners failing to identify patches on the patient’s skin, and more. 

We can implement safe medication practices to reduce these types of errors. When patients are admitted, a thorough medication reconciliation should be performed, as well as a full skin assessment to identify medication patches. A patients pain status should be identified as acute or chronic and opioid status document as naïve or tolerant. See the Targeted Medication Safety Best Practices for Hospitals [#15]. 

When patches are being prescribed, the indication and appropriateness should be also assessed. Within electronic prescribing systems, prescribers should create medication patch order sentences that include the appropriate application frequency. 

To avoid confusion with the oral contraceptive Xulane, make sure the word “patch” is included in the computer order entry. Barcode scanning should always be implemented to ensure correct product selection. Documentation of the patch location should be included in the medication administration record (MAR) to ensure appropriate identification and removal. 

Patients should be provided verbal and written education to both patients and caregivers on the use of patches (eg, when to remove and replace the patch) as well as any related safety concerns and error potential. Prescribers should verify patient understanding. 

Health care professionals should remind patients and caregivers to read the accompanying leaflet or Patient Instructions before using the patches. Additionally, teach patients and caregivers to safely discard used or unneeded patches according to guidance in the prescribing information.

For a full list of transdermal patch safety recommendations see ISMP’s Medication Safety Alert! Volume 26, Issue 5.

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