# Another medical question: About dosage droppers **URL:** \ **Category:** Factual Questions\ **Created:** [October 23, 2000, 2:24am UTC](https://boards.straightdope.com/t/another-medical-question-about-dosage-droppers/37933 "2000-10-23T02:24:28Z")\ **Posts on this page:** 10\ **Page:** 1
**Author:** ![Shirley\_Ujest](https://avatars.discourse-cdn.com/v4/letter/s/45deac/32.png) [@Shirley\_Ujest](https://boards.straightdope.com/u/Shirley_Ujest)\ **Post date:** [October 23, 2000, 2:24am UTC](https://boards.straightdope.com/t/another-medical-question-about-dosage-droppers/37933/1 "2000-10-23T02:24:28Z")
Will someone make sense of something that has been driving me nuts every since I noticed it, which occured, btw, when my son had his first cold. I have here before me a bottle of children’s advil. The instructions say 1 \*\*tsp \*\* for the dose. However, the dropper thingy they supply you with is in _mL_ .4, .8 and so on. I have seen this on several bottles, and I have a few here at my house, like five because of a recent cold epidemic, and even my husband has noticed this. Why kitchen measurements for the instructions and metric dosage for the dropper? ---
**Author:** ![peace](https://avatars.discourse-cdn.com/v4/letter/p/c68b51/32.png) [@peace](https://boards.straightdope.com/u/peace)\ **Post date:** [October 23, 2000, 3:01am UTC](https://boards.straightdope.com/t/another-medical-question-about-dosage-droppers/37933/2 "2000-10-23T03:01:13Z")
One tablespoon equals 11.1 ml. They apply metric scale to the bottle because it’s cool, i.e., for prestige. They use “tablespoon” because Americans are the only industrialized nation which still uses obsolete measures and they do not expect American mom to understand mls. Using metric means going with the rest of the world. Besides, ‘fluid’ industry (beverages) already switched to metric. Even hard liquor is measured in metric first, in English second. ---
**Author:** ![KarlGauss](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/karlgauss/32/3713_2.png) [@KarlGauss](https://boards.straightdope.com/u/KarlGauss)\ **Post date:** [October 23, 2000, 3:10am UTC](https://boards.straightdope.com/t/another-medical-question-about-dosage-droppers/37933/3 "2000-10-23T03:10:41Z")
> [@](#): > > \*Originally posted by peace \* > \*\*One tablespoon equals 11.1 ml. > \*\* I disagree. One tablespoon equals 15 ml (well, actually, about 14.7 ml but who’s counting). ---
**Author:** ![peace](https://avatars.discourse-cdn.com/v4/letter/p/c68b51/32.png) [@peace](https://boards.straightdope.com/u/peace)\ **Post date:** [October 23, 2000, 3:51am UTC](https://boards.straightdope.com/t/another-medical-question-about-dosage-droppers/37933/4 "2000-10-23T03:51:27Z")
tablespoon or tablespoonful (tbsp, tblsp, or Tsp) [2] a unit of volume used in bartending. U.S. bartenders use a tablespoon of 3/8 fluid ounce or 1/4 jigger; this is equivalent to about 11.1 milliliters. This is a quote from “The units of Measurments” web page > **[The University of North Carolina at Chapel Hill](https://www.unc.edu/)** > > The University of North Carolina at Chapel Hill, the nation’s first public university, is a global higher education leader known for innovative teaching, research and public service. A member of the prestigious Association of American Universities,... ---
**Author:** ![peace](https://avatars.discourse-cdn.com/v4/letter/p/c68b51/32.png) [@peace](https://boards.straightdope.com/u/peace)\ **Post date:** [October 23, 2000, 3:54am UTC](https://boards.straightdope.com/t/another-medical-question-about-dosage-droppers/37933/5 "2000-10-23T03:54:23Z")
[http://www.unc.edu/~rowlett/units/dictT.html](http://www.unc.edu/~rowlett/units/dictT.html) ---
**Author:** ![KarlGauss](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/karlgauss/32/3713_2.png) [@KarlGauss](https://boards.straightdope.com/u/KarlGauss)\ **Post date:** [October 23, 2000, 4:08am UTC](https://boards.straightdope.com/t/another-medical-question-about-dosage-droppers/37933/6 "2000-10-23T04:08:00Z")
Well, your cites of sites notwithstanding, I still disagree. In Medicine, 1 tbsp is conisdered equivalent to 15 ml and 1 tsp equal to 5 ml. Searching Yahoo for the combination of millilitres and tablespoon gives many surprising (actually startling) disparities for the conversion. Is there one “official” source, A gold standard? Regardless, common clinical usage has one tablespoon equal to 15 ml. Any pharmacists out there? ---
**Author:** ![Shirley\_Ujest](https://avatars.discourse-cdn.com/v4/letter/s/45deac/32.png) [@Shirley\_Ujest](https://boards.straightdope.com/u/Shirley_Ujest)\ **Post date:** [October 23, 2000, 4:53am UTC](https://boards.straightdope.com/t/another-medical-question-about-dosage-droppers/37933/7 "2000-10-23T04:53:27Z")
How about why using two different languages of measurement? That part is really confusing. ---
**Author:** ![The\_Mermaid](https://avatars.discourse-cdn.com/v4/letter/t/a183cd/32.png) [@The\_Mermaid](https://boards.straightdope.com/u/The_Mermaid)\ **Post date:** [October 23, 2000, 3:34pm UTC](https://boards.straightdope.com/t/another-medical-question-about-dosage-droppers/37933/8 "2000-10-23T15:34:11Z")
Milligram (mg) is a measure of dosage Milliliter(ml),cubic centimeter (cc) tablespoon(tbsp) and teaspoon(tsp) are all measures of volume. All liquid medications are measured in dosage per volume ratio. i.e. 1 mg/1ml means there is one milligram in one milliliter of solution. Different medications have different ratios. Infant med have a lower ratio per volume than children’s formuations. Iv meds are measured in this way also. ---
**Author:** ![peace](https://avatars.discourse-cdn.com/v4/letter/p/c68b51/32.png) [@peace](https://boards.straightdope.com/u/peace)\ **Post date:** [October 23, 2000, 5:04pm UTC](https://boards.straightdope.com/t/another-medical-question-about-dosage-droppers/37933/9 "2000-10-23T17:04:23Z")
Shirley, relax: whether you use 11.1, 12.0, or 15.0ml per tbs for conversion, is immaterial. It would be so even with much stronger, prescription, schedule 2 medication, like morphine. OTC Advil won’t make any difference. Ideally, a drug should be prescribed based on individual’s weight, not just as “XYZ every 6 hours”. If your dispenser has 4x marks, go with 12.0ml. In general, there is only one ml, which is 0.001 of a liter, which originates from a meter, which is 1/40,000,000,000 of the Earth meridian, which is a pretty precise and stable measurment. There are many tablespoons, cups, bushels, etc. This is one of the reasons all civilized countries switched to metric system and SI. It’s easier to use with medications, nuts, bolts, drinks, etc. E.g., a calorie (or a kilocalorie, kcal), in which an energetic value of food is measured, originates from a meter, too. So, it makes sence to count calories per gram or kilogram, not per ounce or pound. I can tell you how much booze there is in a standard one-half liter bottle of vodka in 0.5 secs. Can you tell me the same about 1 pint bottle? In pounds? Or: if one gallon of paimt can cover 2000 square yards, how much paint do you have to buy to paint 2 acres? ---
**Author:** ![Another\_County\_Heard\_From](https://avatars.discourse-cdn.com/v4/letter/a/71c47a/32.png) [@Another\_County\_Heard\_From](https://boards.straightdope.com/u/Another_County_Heard_From)\ **Post date:** [October 23, 2000, 5:40pm UTC](https://boards.straightdope.com/t/another-medical-question-about-dosage-droppers/37933/10 "2000-10-23T17:40:52Z")
1. I agree with Karl Gauss on common conversions in medical practice: 1 tsp = 5 ml 1Tbsp = 15 ml 1 fl. oz. = 30 ml and since a 12 fl oz soda is usually 353 or 354 ml, this seems pretty accurate. 2. Mojo57 says: > [@](#): > > Different medications have different ratios. Infant med have a lower ratio per volume than children’s formuations. This is a dangerous, but common, misperception. Infant Tylenol, dosed with a dropper, is 80 mg/.8 ml, or 100 mg/ml. Childrens Tylenol, dosed with a spoon, is 160 mg/5 ml, or 32 mg/ml. btw, a spoon with a hollow handle is much better at measuring an accurate dose than a spoon out of your cutlery drawer.