The wrong spoon for the job - medication errors and silverware

Photo by Charles Simmins

Liquid medication is dispensed with dosage instructions similar to "Take one tablespoon every 4 hours". The silverware drawer in the kitchen contains a wide variety of spoons, teaspoons, tablespoons, soup spoons and others with different shapes and uses. Is that tablespoon in the drawer what the doctor meant for you to use?

 The answer is no. The use of measurements such as tablespoon and teaspoon for medication dosages refers to the specific measuring spoon as used in cooking and baking. Any other spoon, despite the similar name, may be larger or smaller than the dosage needed.

A letter published in the Annals of Internal Medicine from food safety researchers Brian Wansink, PhD; and Koert van Ittersum, PhD discusses the results of research on dosing errors because of the use of kitchen spoons. The team discovered that even educated and trained participants would make errors attempting to pour a given amount of liquid into a spoon. Depending on the size of the kitchen spoon, the errors ranged on average from 8% too little to 14% too much.

With many medications, the error may have little consequence for an adult. Children's dosages are often exact and an error can under-medicate the child, or over-medicate them. Since medications may be taken as often as every four hours for several days, the accumulated error can also become significant.

 The Food & Drug Administration has long recommended the use of precise measuring instruments. The researchers agree with this recommendation and suggest "using a proper device -- a measuring cap or dropper, or dosing spoon or syringe -- to measure liquid medicine".