Medication Dosages in Metric

Dear Lisa,

When I have to give my baby medication, I find that all of the measurements are in “cc” or “ml”. Can you tell me what these measurements equal? How much is a teaspoon equal to?

“Please Clarify Metric”

Dear “Please Clarify Metric”,

One Tablespoon = 15 ml
One teaspoon = 5 ml
3/4 teaspoon = 3.75 ml
1/2 teaspoon = 2.5 ml
¼ teaspoon = 1.25 ml
1/8 teaspoon = 0.625 ml
One ounce = 30 ml
1 ml = 1 cc (they are interchangeable).
0.5 ml = ½ ml
0.5 teaspoon = ½ teaspoon
0.25 ml = ¼ ml
0.25 teaspoon = ¼ teaspoon

In pediatrics, many times a parent will be asked to give their child “point 5 of a milliliter” or “point 5 of a cc”. Be careful and watch for the word “point” because this means less than one measure. “Point 5 of a milliliter” stands for one half of a milliliter which is less than 1 ml. Many medication errors occur because proper attention is not paid to the word “point”.

Just to give you a visual, any measurement less than 1.0 ml is less than ¼ of a teaspoon. For example when you give your baby a dropperful of Tylenol and you fill the medication up to the 0.8 ml line, this is equivalent to a little more than 1/8 teaspoon.

Now for some fun with mixed amounts:

One and one quarter teaspoon is 5 ml + 1.25 ml = 6.25 ml.
One and one half teaspoon is 5 ml + 2.5 ml = 7.5 ml.

A word of caution, if you are giving your child a medication and the dosage is greater than a normal adult dose, chances are it is too much and you should recheck the dose. If the medication is equal to an adult dose, in most cases this may also be an error and you should also recheck the dose. If you are giving a child a medication with a dropper and you need to go back to the bottle to fill up the dropper again, recheck the dose to make sure it is the correct dosage. If you are ever giving a child a medication using a Tablespoon, recheck the dose, most medications for children are given in teaspoons not Tablespoons.

It is always better to recheck a medication dosage if there is ever a question. If a medication dosage doesn’t seem right, it is better to err on the side of caution and recheck with your child’s Doctor and Pharmacist who can verify that the dosage is correct. If you ever give the wrong amount of medication to your child call your child' s Doctor and Poison Control at
1-800-222-1222.

Lisa-ann Kelly R.N., P.N.P.,C.
Certified Pediatric Nurse Practitioner

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