Study Finds Dosing Errors of Liquid Medication Common When Using Kitchen Spoons

The Food and Drug Administration is warning consumers to be careful of which kitchen spoons they use when dispensing liquid medication. In fact, the FDA is advising consumers to avoid using kitchen utensils altogether to dose liquid medicines because of recent research that shows that varying sizes of a kitchen spoons frequently leads to over- or under-dosing of medications.

The study, performed by Brian Wansink at Cornell University and colleagues, asked 195 university students to pour 5 mL (1 teaspoon) of liquid cold medication into varying kitchen spoons. To show the students what 5 mL looks like, the researchers first gave the students a full bottle of medication and asked them to pour the 5 mL dosage into a 5 mL teaspoon. Afterward, the students were either asked to pour the same 5 mL dose into a medium or large size kitchen spoon. After each pour, each student was asked how confident they were that they had poured the correct amount.

Overall, the results of the study showed that the amount of cold medicine that the participants poured varied directly with the size of the kitchen spoon used. For example, the students overdosed by 11.6% when using the larger kitchen spoon and under-dosed by 8.4% when using the medium-sized kitchen spoon. In both cases, all the students felt very confident that they poured the correct dosage.

While the researchers admit that the consequences from a single dosage error are minor, under- and overdosing errors are more likely to occur in tired and sick individuals who are dosing themselves every four to eight hours for several days at a time. Over that extended time period, the dosing errors can accumulate and cause more moderate to severe complications. The researchers concluded that it is best for patients to use a measuring cap, dosing spoon, measuring dropper, or dosage syringe to dispense liquid medication.