Limitations of e-Prescribing Standards

John D. HalamkaThe following is an important guest post from Dr. Marvin Harper, CMIO at Boston Children's Hospital, identifying a gap in e-prescribing standards:

Why am I guest writing a blog post here?   As a practicing pediatrician and CMIO at Boston Children’s Hospital I am particularly sensitive to specific limitations of current e-prescribing standards.

Being able to write and route prescriptions electronically provides many advantages over the handwritten paper prescription process that inherently uses families as couriers.  Nonetheless the current standards for e-prescribing have created a void that permits limitations in certified vendor software on both the prescribing and pharmacy receiving side. The result is that our patients are not yet benefiting from the full potential of eprescribing. Additional national standards for electronic prescription transmission are needed to provide the common ground needed by software vendors at each stage of the prescription life cycle.

The core elements to consider when writing a prescription are the name of the medication, the dose form (e.g., capsules, tablets, extended release tablets, liquids), the amount of medication the patient should take at each dose, the dose frequency (e.g., once, twice or three times per day) and the duration of time for the patient to take this medication.

Currently there are no standards for provision, transmission, receipt or display of weight within electronic prescriptions. To prescribe the correct quantity per dose of the desired medication the weight based dose is converted to a finite dose using a recent, appropriate, and reliable patient weight. This is then converted to an appropriate drug volume dose (e.g., one tablet, five milliliters) based on the drug product selected (e.g. amoxicillin 500 mg capsule or amoxicillin 250 mg/5 mL suspension). Considering all of these manipulations, it is then obvious that in order for a pharmacist to review and verify that the correct dose is being dispensed, in addition to the medication and finite dose, the pharmacist needs to have the prescriber’s target weight based dose and the patient weight available at the time of review. Stated another way, providing the weight is not fully sufficient for the pharmacist to verify the intended target weight based dose. With today’s standard the pharmacist only gets a volumetric dose  (e.g., 5 mL) which is then inferred into a strength dose (e.g., mg/kg) from the prescribed formulation. It is therefore impossible for a pharmacist to fully verify that prescribed doses are appropriate for their pediatric patients.

The current limitation for the entire prescription sig line within a prescription to be transmitted electronically is 140 characters. Basically a tweet. Not close to enough for many prescriptions. As a result we must continue to provide some prescriptions on paper to the patient.

Many commonly prescribed medications require slowly increasing or decreasing the finite dose. These are commonly referred to as medication titrations or tapers and are therapeutically very important to avoid secondary complications. It can be complex to transfer this information satisfactorily to patients and the pharmacist in the best of circumstances. It is impossible with a 140 character limit to the sig.  In my experience within pediatrics this is most problematic for prescribing anticonvulsants, steroids, and immunosuppressive medications.

Did I mention the current limitation for the sig line within a prescription to be transmitted electronically is 140 characters. Basically a tweet. Not close to enough. It is not possible to provide a compounding recipe within 140 characters. Why do we need to write prescriptions for compounded medications? Not all patients can take medications in the dose forms available domestically from pharmaceutical companies. As a result some medications must be compounded (typically crushed and mixed with other ingredients). In pediatrics, compounding is most often required to make the medication available in a liquid form for patients unable to swallow a pill. This may also apply to adults, especially those needing to receive medications via feeding tubes. Occasionally medications must be compounded for other reasons such as palatability or patient allergies.

As uses of medications expand beyond traditional indications, in order for a pharmacist to truly review and verify a prescription order, in addition to mathematical checking, it is critical for a pharmacist to know what the medication is being used for to ensure that the prescribed dose is within the recommended range for any particular indication.  Different indications often require vastly different doses of a medication.

Access to known allergies the patient may have to medications and increasingly access to patient genetic information relating to drug metabolism or adverse reactions can help assure that patients receive the safest medications and doses.

In summary it is important that additional standards for expected eprescribe capabilities are defined for vendors providing prescription writing software, the transmission of prescriptions and the software utilized by pharmacists receiving prescriptions. Most importantly, in my mind, are capabilities to transmit the weight, target weight based dose and more space for the electronic sig to accommodate information needed for medication tapers and compounding.

Limitations of e-Prescribing Standards was first published by Dr. John D. Halamka in his blog, Life as a Healthcare CIO and it is reprinted by Open Health News under the terms of the Creative Commons Attribution-Noncommercial-Share Alike 3.0 United States License. The original post can be found here.