Dangerous Dosing Errors Rampant Among Parents Measuring Liquid Medications

Medications for children are usually available in liquid form, with dosage based on children’s body weights. It is therefore critical for parents to measure the correct dose of these medications to avoid giving a dose too small or too large to their children.

Parents who give their children lower than the prescribed dose run the risk of the treatment being ineffective. Medication overdoses, on the other hand, lead to more than 71,000 emergency room visits among children each year[1] and can be life-threatening.

Poorly designed drug labels and packages for children’s liquid medications have been implicated in parents’ dosing errors. The Food and Drug Administration recommends that parents use dosing tools with standard markings to measure children’s liquid medications, but no national guidelines exist on which type of dosing tool is best.

A new federally funded, randomized clinical trial, published in the October 2016 issue of Pediatrics,[2] found that many parents measured the wrong dose of liquid medications for their children, and these errors varied depending on the dosing tools and units of measurement they used.

The new trial

The trial involved approximately 2,100 parents (or adult legal guardians) of children age 8 or younger in three university-affiliated pediatric outpatient clinics. Each parent measured nine doses of oral liquid medications using different dosing tools (a 30 milliliter cup or 10 milliliter oral syringes) and dose measurement units (milliliters or teaspoons). Measurement units on the medication labels differed from those described in the dosing tool in some of the exercises.

Across all of these nine exercises, more than four in five parents made at least one dosing error that was 20 percent lower or higher than the assigned dose, regardless of the measurement units or dosing tools that they were asked to use. Moreover, one in five made at least one large error, defined as more than double the assigned dose.

Slightly more than two-thirds of all errors involved overdosing. However, there was a significant trend toward fewer errors as parents worked through the nine dosing exercises, indicating a learning effect.

Although some errors occurred with oral syringes, far more errors occurred with the dosing cup, a finding that was consistent across subjects with various health literacy levels as well as English and Spanish speakers. All in all, parents who used the dosing cup were almost five times more likely to make a dosing error, compared with those who used oral syringes.

The researchers explained that one reason use of dosing cups may be inferior to use of oral syringes is that the same distance along the side of the tool represents a greater volume for cups than syringes, making oral syringes much more precise measuring tools than dosing cups. In addition, when cups are not held at eye level, they may appear to be filled to a particular level when they are not.

Parents who received medication labels with teaspoon-only dosing directions and dosing tools marked with both milliliter and teaspoon units made significantly more errors than those who received labels with millileter-only dosing directions and tools marked with millileter units only. This finding supports the researchers’ hypothesis that unit mismatches between dosing tools and drug labels increase the risk of errors.

The trial findings also support the 2015 recommendation of the American Academy of Pediatrics (AAP) regarding the exclusive use of the milliliter system for children’s oral liquid medications.[3]

The researchers went one step beyond the AAP recommendation, though, encouraging the use of oral syringes for measuring liquid medications, particularly for smaller doses: “[T]his change would probably benefit all families, regardless of health literacy and language.”

What You Can Do

To minimize dosing errors when administering children’s liquid medications, ask your family doctor or pediatrician to write the dosages for both prescription and over-the-counter oral liquid medications in milliliters, and to review these dosages with you. Use small-volume oral syringes with clear milliliter markings to accurately measure these medications.

Never administer liquid medications to a child using household spoons, because they vary widely in size and shape, resulting in dosing errors.

If your child’s liquid medication comes with a dosing cup, dropper, teaspoon or tablespoon, it is best to ask your pharmacist for an oral syringe to replace these tools.

If needed, ask your pharmacist to show you how to measure each dose of your child’s liquid medication. Ask your pharmacist to use pictures or drawings or to demonstrate measuring the right dose.

Another way to ensure that you will administer the right dose is to draw a line or apply a piece of tape on the syringe corresponding with the correct dose before measuring out the medication.

Always check the name and dose of every medication three times before administering to anyone.

Save the Poison Help Line number (800-222-1222) on your phone and put it in a noticeable place in your kitchen. In addition to medication-related emergencies, you can call this number with questions about how to properly administer medications.

References

[1] Schillie S, Shehab N, Thomas K, Budnitz D. Medication overdoses leading to emergency department visits among children. Am J Prev Med. 2009;37(3):181-187.

[2] Yin HS, Parker RM, Sanders LM, et al. Liquid medication errors and dosing tools: A randomized controlled experiment. Pediatrics. 2016;138(4):e20160357.

[3] Paul IM, Neville K, Galinkin JL, et al. Metric units and the preferred dosing of orally administered liquid medications. Pediatrics. 2015;135(4):784-787.