Labeling of transdermal scopolamine products
A pharmacist was replacing transdermal scopolamine, an anticholinergic agent, in an automated dispensing cabinet (ADC) and noticed that the replacement product (from Perrigo) expressed the amount of drug in terms of how much was released over 3 days (1 mg/3 days). In the past, the transdermal scopolamine they purchased (from Sandoz) had been labeled in terms of the amount of scopolamine contained in the patch (1.5 mg).
Also, the hospital's electronic order entry system listed transdermal scopolamine as 1.5 mg and displayed this amount on the medication administration record (MAR) and the ADC screen, which is inconsistent with the current package labeling from Perrigo.
The pharmacist thought that perhaps this was a new strength of scopolamine, but he noticed that online drug references such as Lexicomp and Micromedex indicate that a 1.5 mg patch delivers 1 mg of scopolamine over 3 days.
This situation can confuse pharmacists and nurses. However, a US FDA draft guidance (http://www.ismp.org/ext/774) has called for the strength of transdermal products to be expressed as a rate (for example, 1 mg/3 days), instead of total drug content (for example, 1.5 mg). The FDA has been working to change all transdermal scopolamine product labeling to 1 mg/3 days rather than 1.5 mg.
Until the labeling of all transdermal scopolamine products displays the new strength expression and older stock has been exhausted, the potential for confusion exists.
Consider editing order entry systems, order sets, and MARs to indicate the drug delivery rate of 1 mg over 3 days, and include a default note on the order that states, "1.5 mg = 1 mg/3 days."
Errors with injectable specialty medications
Multiple errors and hazards related to the quantity and package size of specialty medications have been reported to the Institute for Safe Medication Practices (ISMP). For example, an outpatient pharmacy dispensed two syringes of the human interleukin-12 and -23 antagonist STELARA (ustekinumab) 45 mg/0.5 mL because the data entry technician mistakenly entered a quantity of "1" for one syringe, not realizing that Stelara is billed (and dispensed) per mL. This resulted in 1 mL, or two syringes, being dispensed.
According to the National Council for Prescription Drug Programs Billing Unit Exception Task Group, liquid medications (including injectables) are dispensed based on standardized "billing units." The "mL" billing unit is used when a product is measured by its liquid volume, as seen with Stelara. However, injectable products may also be billed as a "kit" containing a single syringe or pen with an alcohol swab, or a tray containing multiple syringes or pens with alcohol swabs (http://www.ismp.org/ext/817). One challenge with selecting the correct billing unit is that the pharmacy staff may not be aware of the exact contents inside each carton since these are usually not opened.
To learn more about specialty medication quantity and package size errors and hazards, ISMP sent a targeted five-question survey to 36 specialty pharmacies. Sixty-four percent (N = 23) of pharmacies responded to the survey. Ninety-six percent of the respondents said they were aware of errors or close calls related to specialty injectable medication quantities or package sizes. The most common concerns were associated with confusion regarding whether the billing standard was based on "milliliters" or "kits," actual starter pack quantities, and when multiple syringes were needed for one dose. The specialty medications cited most frequently by respondents as being involved in events were DUPIXENT (dupilumab), HUMIRA (adalimumab), CIMZIA (certolizumab pegol), and SKYRIZI (risankizumab-rzaa).
Respondents also shared strategies to prevent errors related to quantity and package sizes. One in three pharmacies indicated that they use dispensing software notes to alert the team to the correct package size of specific products (for example, quantity 1 = 2 syringes).
Nearly one in five pharmacies requires two pharmacists to double-check the entry of all orders for specialty drugs. Two pharmacies suggested the use of a proactive risk assessment to evaluate the package size prior to dispensing a new medication, and two pharmacies said they employed bar code scanning to detect package size discrepancies. Other notable strategies include clarifying the billing unit as "mL" versus "kit" in the dispensing system, adding a default package size to the dispensing software, printing the number of labels based on the number of packages needed, and taping packages together. Prescribers should include the units (mL versus syringe versus box versus kit) with the quantity to minimize pharmacy staff confusion.