Mary Poppins may have been right about a “spoonful” of sugar helping the medicine go down. But dosing important and often concentrated medications by the “spoonful” isn’t really helpful to patients or parents. The problem is that the “spoonful” is a variable measuring device. Spoons, typical household spoons with which we scoop our cereal and sip our soup, have not been designed to deliver consistent dosages of medications. Nevertheless, such silverware still seems to be utilized far too often when measuring out liquid prescriptions and OTC products.
A study recently published in the journal Pediatrics, the official journal of the American Academy of Pediatrics, demonstrated that parents using teaspoons or tablespoons to measure out medication had twice the likelihood of making an error in dosing.
A teaspoonful is generally considered to be 5ml of liquid. A tablespoonful is considered to be 15ml. However, the actual volume which YOUR household teaspoon or tablespoon holds might be quite different, ranging anywhere from 3ml to 7ml according to various research. Consequently most pharmacies will dispense a “measuring spoon” “oral syringe” or “dosing cup” with liquid medication in order to promote a more accurate measurement. OTC liquid medications like liquid Tylenol or Advil are often sold with a dosing cup on the top.
Prescriptions that arrive at the pharmacy with directions that state: Take 1 teaspoonful by mouth 3 times daily are often changed by the pharmacy to read something like this:
Take 1 teaspoonful (5ml) by mouth 3 times daily.
That makes the dosage a bit more clear.
BUT…this study raises a question in my mind: Should we even use the word “teaspoonful” or “tablespoonful” on the prescription label at all? Does the very fact that the word “teaspoonful” or “tablespoonful” appears make it more likely that patients will revert to the use of their kitchen spoon if the handy dosing device isn’t available or convenient? Are we, as pharmacists, implying that 1 teaspoonful always equals 5ml by wording out labels this way?
What if we changed the directions to say this?
Take exactly 5ml (150mg) by mouth 3 times daily. Use accompanying dosing device.
What message are we giving with those directions? Does it convey a more serious approach to the dosing of our liquid medications? Personally, I think it does. Changing the way we think about labeling our liquid medications won’t come easy. Old habits die hard. But studies like this make me think now is the time get serious about it.
Personally (this is my opinion here) I think that best practices when it comes to dispensing of liquid prescription medications should be to:
1) Specify the directions in terms of metric units (5ml, 10ml, etc.) and NOT include words like teaspoonful/tablespoonful
2) Specify the amount of medication delivered by that dose (250mg, 500mg, etc.)
3) Always include 2 dosing devices (measuring cup, oral syringe, dropper-style device or calibrated spoon)
4) Always counsel patients on the use of such devices for accurate measurements
What are your thoughts? Should we eliminate the word “teaspoonful” or “tablespoonful” from medication labels altogether? Is that going to far? I suppose if you are Mary Poppins, who is practically perfect in every way, dosing sugar by the teaspoonful is still okay. But for the rest of us, I think this is an issue worth thinking more seriously about.
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dosing Measuring prescription medicine Prescription Drugs spoons and dosages
Last modified: October 30, 2014