Pharmacy News

Standardize Units for Dosing Liquid Oral Prescription Medicines, Task Group Says

[July 1, 2014, AJHP News]

Kate Traynor

BETHESDA, MD 12 Jun 2014—An organization best known for setting standards for the electronic exchange of pharmacy data released recommendations in April calling for pharmacies to eliminate nonmetric units of measure on the labels of prescription liquid oral medications.

The recommendations, published by the National Council for Prescription Drug Programs (NCPDP), would also apply standard nomenclature to other elements of the "transcribing, labeling, dispensing, and administering" of liquid oral medications, essentially establishing the same practices used in hospitals.

Under NCPDP's proposal, the standard volumetric unit is the milliliter, which should always be abbreviated mL; designations such as "cc" should never be used. Dosing devices should display the same standardized units as the container label and the instructions to patients and should be dispensed along with each filled prescription.

The recommendations also state that container labels should always display leading zeros in front of a decimal point for volumes less than 1 mL, and trailing zeros should never be used.

"Standardizing the dosing designation, making sure patients and caregivers have access to appropriate dosing devices and understand why proper dosing is so important, will go a long way in helping to prevent underdosing and overdosing and improve patient health outcomes," stated NCPDP President Lee Ann Stember.

Daniel Budnitz, director of the Medication Safety Program at the Centers for Disease Control and Prevention (CDC), said the long-term goal of the recommendations is "to try to reduce the number of errors and harmful overdoses in children," whose medications are often formulated as liquids.

Daniel Budnitz

The recommendations were developed by a working group with representatives from CDC, FDA, drug manufacturers, pharmacies, ASHP, and several other stakeholders.

Budnitz said NCPDP was asked to host the collaborative effort because of the organization's previous work with stakeholders to eliminate the abbreviation "APAP" from the labels of acetaminophen-containing prescription medicines.

Task group member Cynthia Fitzpatrick of FDA's professional affairs and stakeholder engagement team—which operates the agency's Safe Use Initiative—noted that the recommendations in the report are "voluntary for the pharmacy stakeholders" and have no regulatory force.

Nevertheless, Fitzpatrick said, "we hope that pharmacists will not only follow the recommendations . . . but that they will also make sure that their patients have the appropriate dosing device and that before they leave the pharmacy, they'll understand how to use and measure the medicine."

By mid-May, chain pharmacies representing a total of about 16,000 individual stores had committed to following the recommendations, according Dan Ramirez, industry consultant for McNeil Consumer Healthcare and the task group leader for the project.

Dosing errors. Budnitz said the NCPDP project grew out of CDC's Preventing Overdoses & Treatment Errors in Children Taskforce (PROTECT) initiative, a public–private partnership whose goal is to reduce unintentional drug overdosages in children. He said PROTECT had determined that "the most common dosing error was when parents were confused about reading the dosing instructions."

"There needs to be some education of parents . . . and that's a role that I think pharmacists can play when they dispense medications," Budnitz noted.

Gaylord Lopez, executive director of the Georgia Poison Center, said dosing errors are "a real problem that poison centers face on a daily basis."

Gaylord Lopez

More than 16,000 cases of therapeutic mistakes resulting from "confused units of measure" or "dispensing cup errors" were reported to poison control centers in 2012, according to the most recent annual report from the American Association of Poison Control Centers. Most of the reports involved children, and the highest proportion affected children age five years or younger.

"We see these cases. We see them with both prescription and over-the-counter-type products," Lopez said.

Lopez, who was not part of the NCPDP task group, said that a standardized approach is needed to reduce dosing errors. He said parents and caretakers also need help understanding how to correctly measure and administer liquid medications.

"This medication dosing error problem should really be a nonissue," he said.

Dosing devices. Budnitz said one goal of the task group was to end the use of "kitchen measures" like teaspoon and tablespoon in the labels and instructions for prescription liquid medications. He said these terms imply to parents that they can "grab a [kitchen] spoon and use it to dose medicines, which is not the most accurate way to do it."

But even devices intended for measuring liquid medications have problems, such as displaying multiple types of units, including units that bear no relation to the instructions for dosing the medication.

"There are a lot of different dosing devices out there, and some of them are just horrible," said ASHP Assistant Vice President and NCPDP task group member Gerald McEvoy.

Gerry McEvoyl

"There are dosing cups, for example, that have drams on them. And no one even writes a prescription in drams anymore, let alone would expect anyone to understand what that means and to measure it," McEvoy said.

FDA's Fitzpatrick said manufacturers for many years have included multiple different units on dosing devices to allow for their use with any liquid medication, regardless of the unit on the package and instructions.

NCPDP's recommendations note that the inclusion of units other than milliliter on dosing devices has led to dosing errors by health care professionals, patients, and caregivers.

Authority. Fitzpatrick emphasized that her contributions to the task group were as an equal collaborator, not a regulator.

"We don't control all of the elements or the format" of the container labels for prescription drugs, Fitzpatrick explained. "Most of that responsibility lies with the states."

McEvoy said the task group was initially concerned that pharmacists might not have the authority under state law to use "mL" on drug containers if, for example, the prescription was written for teaspoons.

"But the National Association of Boards of Pharmacy (NABP) actually reviewed all of the practice laws and regulations and determined there was nothing that precluded that professional prerogative," McEvoy said.

An NABP representative was part of the NCPDP task group. The recommendations note that NABP "endorses the use of mL and supports pharmacists in exercising professional judgment to select mL as the preferred unit of measure."

But the recommendations note that some pharmacy information systems may not be configured to convert between units. The document encourages pharmacy software system developers to resolve any such limitations as quickly as possible to remove this potential barrier to implementing the recommendations.


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