1. Shastay, Ann MSN, RN, AOCN

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In 2015, The Medicines Company announced the U.S. Food and Drug Administration (FDA) had approved IONSYS, a patient-controlled transdermal iontophoretic system that releases fentaNYL on demand. The system is composed of a plastic housing that contains the battery and a separate hydrogel reservoir that contains fentaNYL. The patient activates a dose by pushing a button twice on the credit card-size device that adheres to the skin, which causes an imperceptible electrical current that drives fentaNYL through the skin by iontophoresis. The product is limited to hospital use only, for short-term management of acute postoperative pain in adult patients. Ionsys was first approved by FDA in 2006 but was never marketed in the United States. It had been marketed in Europe but was withdrawn due to corrosion that might cause release of fentaNYL without pushing the button. The company told us improvements have been made to address this issue. Still, in the Supplemental New Drug Application approved by the U.S. FDA, the company was called upon to monitor this possibility and submit findings regularly. The company said no changes have been made to dosing information in the previously approved labeling. Each activation delivers 40 mcg of fentaNYL over 10 minutes, up to six times an hour. Thus, up to 240 mcg per hour can be administered and drug delivery can be activated up to 80 times per 24 hours. Excessive button pushes can lead to serious injury. The used device is removed and replaced every 24 hours for a maximum duration of therapy of 72 hours.


Time to Eliminate Teaspoonfuls

In an ambulatory pharmacy, a prescription was being refilled for cetirizine 1 mg/mL. When checking the medication, the pharmacist noticed the directions read, "Take 2.5 mL (1.2 teaspoonfuls) by mouth once daily." The pharmacist looked at the original prescription and corrected it to read, "Take 2.5 mL (1/2 teaspoonful) by mouth once daily." The prescription had been filled previously with the incorrect directions. Fortunately, the mother had been giving her child the correct dose, measuring 2.5 mL for each dose and not using the incorrect teaspoonful designation. Typing a decimal point instead of a slash mark (1.2 instead of 1/2) can easily happen when tapping the wrong key on the keyboard because the keys are side-by-side. This long-standing problem wouldn't happen if teaspoonfuls were no longer used in dosing directions. Since 2011, Institute for Safe Medication Practices (ISMP) has been calling for the use of mL doses only for all liquid medications. Now, it looks like complete transition to a metric-only measurement system is coming with other groups working toward that goal, including the Centers for Disease Control and Prevention, the National Council for Prescription Drug Programs, and the FDA. More recently, the American Academy of Pediatrics called for mL only to be used when prescribing and administering liquid medications to children.


Perhaps the most important impetus for change can be seen in the 2015 certification criteria for health information technology (IT) systems published in the Federal Register by the Office of the National Coordinator for Health Information Technology (ONC). ONC is calling for IT systems to limit prescribers to use the metric system for all electronic medication orders. That means electronically transmitted prescriptions from doctors' offices will be in mL only. The time has come for lasting change. To prevent confusion, we hope all hospitals and community pharmacies are working toward designating oral liquid doses metrically by only using mL in the patient directions. Patients will need an oral dosing device, such as an oral syringe or dosing cup that measures in mL only. Baxter, NeoMed, and BD have already stated they will be providing oral syringes with mL-only scales. The array of devices with combination markings in Figure 1 will become a thing of the past.

Figure 1 - Click to enlarge in new windowFigure 1. Oral syringes obtained in April 2015 from 5 different large chain pharmacies and 2 independent pharmacies. All are potentially unsafe due to the risk of confusion between the mL and teaspoon scales.

Use Dosing Cups With mL Markings Only

A fatal event was reported to ISMP in which a nurse confused two dosing scales on a plastic oral liquid dosing cup. The nurse measured a dose of morphine sulfate oral solution 20 mg/mL incorrectly for an opioid-naive hospice patient. The nurse misread the scale marked drams as mL and administered 1 dram of the medication, mistakenly believing she was to give 1 mL. One dram is 3.7 mL, so the patient received close to 75 mg of morphine. The patient was found dead a few hours later. In place of cups, oral syringes that measure only in mL should be used for oral liquid medications when possible. If a dosing cup must be used, ideally it should only measure in mL. You may need to rely on cups with mL and household measures until mL-only cups can be supplied.


Lack of e-prescribing interoperability leads to double dosing. A patient was being discharged from the hospital on warfarin 3 mg daily. The prescriber sent an electronic prescription (e-prescription) to the patient's outpatient pharmacy for warfarin with instructions to take three 1-mg tablets daily. When the prescriber realized warfarin was available in a 3-mg tablet strength, he discontinued the first prescription and sent another e-prescription for one 3-mg tablet daily. The pharmacy received and dispensed both prescriptions to the patient. The patient took both, a total of 6 mg of warfarin, daily for several days before visiting an anticoagulation clinic where an elevated international normalized ratio was measured and the error was discovered. The prescriber did not realize that, with e-prescribing, the prescriber must call the pharmacy to cancel the e-prescription, and the patient's medications were not reviewed with the patient before discharge. Although the patient was provided with a discharge medication list, the daily warfarin dose stated to take the medication "as directed." It is uncertain whether the outpatient pharmacy computer system issued a duplicate therapy alert when the second warfarin prescription was entered. The pharmacist did not question the two warfarin prescriptions or clarify the daily dose, perhaps believing that the 1-mg tablets were being provided for titration, and the patient was never counseled when picking up the prescriptions.


Medications prescribed upon discharge must be a priority for discharge education along with a clear demonstration of patient understanding. Consider giving patients discharged on warfarin a free educational leaflet on warfarin available from ISMP ( The consumer leaflet will help patients understand proper medication use, how errors happen, and how errors can be prevented.


For now, prescribers need to know that e-prescriptions sent to outpatient pharmacies cannot be discontinued without calling the pharmacy directly. To address this issue, the Office of the National Coordinator for Health Information Technology Health IT Certification Program has published proposed certification criteria for 2015 that would require e-prescribing systems to notify the pharmacist that a previously sent prescription should be cancelled ( Health IT certification provides assurance to purchasers that a system meets the technology capability, functionality, and security requirements adopted by the Secretary of Health and Human Services. Thus, we can anticipate that vendors will seek to comply with these criteria when the proposed rule becomes a final rule.