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Unregistered
05-27-2006, 12:07 PM
How many drops are in one milliliter?

Robert Fogt
05-27-2006, 02:55 PM
In cooking, a drop is about 0.051 milliliter, specifically it is 1/96th of a teaspoon.

In pharmacies, a drop used to be another name for a minim, which would make it 0.0616 milliliters.

But now the drop is standardized in the metric system to equal exactly 0.05 milliliters.

Unregistered
10-26-2006, 05:07 PM
How many drops are in one milliliter?
How many drops in a minum?

Robert Fogt
10-27-2006, 02:57 AM
In pharmaceutical applications, 1 drop = 1 minum.

Not in cooking though.

Unregistered
01-10-2007, 01:46 PM
In cooking, a drop is about 0.051 milliliter, specifically it is 1/96th of a teaspoon.

In pharmacies, a drop used to be another name for a minim, which would make it 0.0616 milliliters.

But now the drop is standardized in the metric system to equal exactly 0.05 milliliters.

Unregistered
03-25-2007, 11:49 AM
thanks-now I know my infusion rate.

Unregistered
09-10-2007, 11:19 AM
Its 25 drops per ml, you guys are all wrong

Mrs X
09-10-2007, 02:35 PM
Its 25 drops per ml, you guys are all wrong
If it is water, the standard was changed 15 - 20 years ago to make 20 drops = 1mL. The viscosity of most things is temperature dependent, so this would be at room temperature. Hope this helps.

Unregistered
09-11-2007, 10:43 PM
Drop (unit)
For other uses, see Drop.
The drop is a unit of measure of volume, the amount dispensed as one drop from a dropper. It is often used in giving quantities of liquid drugs to patients, and occasionally in cooking.

The volume of a drop is not well-defined: it depends on the device and technique used to produce the drop and on the physical properties of the fluid. This is similar to units like the cup, tablespoon, and teaspoon that depend on the spoon or cup.

There are several exact definitions of a "drop":

the "metric" drop, 1/20 mL (50 μL).
the medical drop, 1/12 mL (83 1/3 μL).
the Imperial drop, 1/36 of a fluidram (1/288 of an Imperial fluid ounce, or 1/1440 of a gill) (approximately 99 μL).
an alternate, possibly apocryphal, definition of the drop is 1/1824 of a gill (approximately 78 μL).
the U.S. drop, 1/60 of a teaspoon or 1/360 of a U.S. fluid ounce (approximately 82 μL).
an alternate definition of the U.S. drop is 1/76 of a teaspoon or 1/456 US fl oz (approximately 65 μL).
According to Webster dictionary, "drop" indicates the smallest volume of a liquid that may be measured. The size of drop may vary with the viscosity of the liquid.

In the past, a drop was another name for a minim. This meaning was used in Pharmacy to describe a volume equal to one 60th of a fluid dram or one 480th of a fluid ounce. This is equal to about 0.0616mL (U.S.) or 0.0592mL (Britain). Pharmacists have since moved to metric measurements, with a drop being rounded to exactly 0.05mL (that is, 20 drops per millilitre). In hospitals, intravenous tubing is used to deliver medication in drops of various sizes ranging from 10 drops/mL to 60 drops/mL. A drop is abbreviated gt, with gtt used for the plural. These abbreviations come from the Latin for drop, gutta.[1] articles.

A drop can also be used less formally as a unit of volume in recipes. According to some older kitchen references, 24 drops = Ľ teaspoon. Using U.S. definitions, this makes the drop equal to about 0.051mL, making it quite comparable to the pharmacist's drop.[1]

^ a b Russ Rowlett. How Many? A Dictionary of Units of Measurement. University of North Carolina (2005-17-11). Retrieved on 2006-09-07.

Unregistered
09-30-2007, 06:27 PM
Drop (unit)
For other uses, see Drop.
The drop is a unit of measure of volume, the amount dispensed as one drop from a dropper. It is often used in giving quantities of liquid drugs to patients, and occasionally in cooking.

The volume of a drop is not well-defined: it depends on the device and technique used to produce the drop and on the physical properties of the fluid. This is similar to units like the cup, tablespoon, and teaspoon that depend on the spoon or cup.

There are several exact definitions of a "drop":

the "metric" drop, 1/20 mL (50 μL).
the medical drop, 1/12 mL (83 1/3 μL).
the Imperial drop, 1/36 of a fluidram (1/288 of an Imperial fluid ounce, or 1/1440 of a gill) (approximately 99 μL).
an alternate, possibly apocryphal, definition of the drop is 1/1824 of a gill (approximately 78 μL).
the U.S. drop, 1/60 of a teaspoon or 1/360 of a U.S. fluid ounce (approximately 82 μL).
an alternate definition of the U.S. drop is 1/76 of a teaspoon or 1/456 US fl oz (approximately 65 μL).
According to Webster dictionary, "drop" indicates the smallest volume of a liquid that may be measured. The size of drop may vary with the viscosity of the liquid.

In the past, a drop was another name for a minim. This meaning was used in Pharmacy to describe a volume equal to one 60th of a fluid dram or one 480th of a fluid ounce. This is equal to about 0.0616mL (U.S.) or 0.0592mL (Britain). Pharmacists have since moved to metric measurements, with a drop being rounded to exactly 0.05mL (that is, 20 drops per millilitre). In hospitals, intravenous tubing is used to deliver medication in drops of various sizes ranging from 10 drops/mL to 60 drops/mL. A drop is abbreviated gt, with gtt used for the plural. These abbreviations come from the Latin for drop, gutta.[1] articles.

A drop can also be used less formally as a unit of volume in recipes. According to some older kitchen references, 24 drops = Ľ teaspoon. Using U.S. definitions, this makes the drop equal to about 0.051mL, making it quite comparable to the pharmacist's drop.[1]

^ a b Russ Rowlett. How Many? A Dictionary of Units of Measurement. University of North Carolina (2005-17-11). Retrieved on 2006-09-07.

I wouldn't use Wikipedia, it isn't always accurate.

Unregistered
11-01-2007, 12:49 PM
If you want to be tickish, the question must be clarified as to a drop "of what" "at what temperature" and "at what pressure" "per whose definition" etc.

Not being tickish, myself, I would have responded-----TWENTY.

[But perhaps you'd rather dispute with the wise old owl over his answer to the question, "How many licks does it take to get to the center of a Tootsie-Pop?"]

Unregistered
11-05-2007, 02:04 PM
How many drops are in one milliliter?Give 700mls over 6 hours. Give 700mls over 6 hours.How many drops are in one ml.

Mrs X
11-06-2007, 12:10 AM
Give 700mls over 6 hours.How many drops are in one ml.
Hi, unless you are dosing a plant, or training to be a nurse, I would leave this to the medical professionals. Not something to get wrong.

If you are fixing up a plant, get the plant shop to show you what to do. If you are training to be a nurse, feel free to resister, and send a private message to me or any of the others who answer questions. I understand not everyone can ask their tutors. :)

Unregistered
01-15-2008, 07:49 PM
[But perhaps you'd rather dispute with the wise old owl over his answer to the question, "How many licks does it take to get to the center of a Tootsie-Pop?"]

And as we all remember, the answer to that is Three!

Unregistered
03-14-2008, 05:34 PM
This question is now very important: the pharmaceutical plans' "bean counters" have produced a "cost savings" (read that as a profit increase) to the plans when they recently decided that there is no spillage and no evapration when providing patients with eye drops AND that they will dispense NO more total drops than are prescribed AND no more than the manufacturers provide in a bottle. Thus, if there are 20 drops per mL and the prescription is written for 3 drops per eye per day(6 drops total per day), a 90 day supply should be 540 drops or 27 mL. If the eye drop manufacturer has only 10 mL bottles to dispense then the plan will only provide 2 bottles for a total of 20 mL or 400 drops at the cost for a 90 day supply. This is a shortfall of 140 drops or about 23 days out of 90 prescribed. The plans will allow a paient to reorder "early", at an additional coet, of course. This results in a 35% increase in costs for the patient. Damn these bean counters!

boyboy1944
03-18-2009, 04:26 AM
How many drops are in one milliliter?
I am curious as to how many drops are in one milliliter

JohnS
03-18-2009, 06:51 AM
I am curious as to how many drops are in one milliliter

See post #9. Pick a definition, pick any definition.

Reality depends on the dropper, the liquid, and the temperature, but there are multiple "standard" definitions between 50 µL and 99 µL per drop (20 to 10 drops per mL).

Unregistered
04-17-2009, 06:01 PM
I just called the pharmicist at CVS and she said 20 drops equal 1 ml.
My baby needs .3 ml of medicine so that's 6 drops (20 x .3 = 6).

Unregistered
05-12-2009, 04:17 PM
I wouldn't use Wikipedia, it isn't always accurate.
Yeah... and forums always are? :o)

Unregistered
06-30-2009, 02:10 PM
Wikipedia is quite accurate here. I called the manufacturer of some eyedrops I am using, and was told that there are 100 eyedrops in a 5ml bottle (20 drops per ml) of one of the medications I am using, while there are 150 drops in a 5ml bottle of another, due to its thinner viscousity.

Close enough to determine how many days, at 4 drops per day, these bottles will last. 25 days for the first, 37.5 for the second.

GreatAstronomer
07-28-2009, 09:44 AM
Wikipedia is definitely accurate here. I remember all this stuff from those boring physics and engineering classes in college...

Unregistered
08-03-2009, 12:48 PM
I find it amusing that two high priests of water drops proclaim different numbers. I have a few theories that could account for that.

1. The size of a water drop varies over time. If this reaches the scientific community, I predict it will blow Einstein's theories out of the water. According to my theory, 65 million years ago, water drops weighed 10 pounds, and it was rain drops that killed the dinosaurs.

2. One high priest was using American drops and the other was using metric drops.

3. Neither one actually counted the drops. They calculated the number of drops theoretically, as part of their college thesis.

I have more than a passing interest in the subject because I use eye drops to prevent glaucoma damage. I took a more unorthodox, and possibly heretical approach. I actually counted the drops. When squoze out of a 5 ml polypropylene bottle that originally contained eye drops, I got 26 drops of room temperature tap water per gram of water.

I think I can safely assume that 1 ml of my tap water weighs very close to 1 gram. As a second check on the quantity of water, 5 grams of water fills the bottle to the same height as an unopened bottle of eye drops. The label of this prescription bottle says it contains 5 ml. I also feel comfortable thinking my jeweler's scale is accurate within 2 %, as it tells me my U.S. nickel weighs 5.0 grams.

So there you have it folks. I guess I should mention that apparently the size of water drops does vary depending on the size of the opening in the bottle, and the material the bottle is made out of.

Unregistered
10-16-2009, 07:08 AM
Hi all....I was mixing some juniper oil in propylene glycol yesterday and needed to know how many drops of that mixture were in 1 mL....firstly I filled my dropper to the 1 mL mark with room temp water and counted the drops which equaled 20 drops exactly....then I took a duplicate dropper and did the same thing but with the juniper/PG solution....this was 40 drops exactly....the specific gravity made quite a difference.

Mrs X
10-16-2009, 04:56 PM
Hi all....I was mixing some juniper oil in propylene glycol yesterday and needed to know how many drops of that mixture were in 1 mL....firstly I filled my dropper to the 1 mL mark with room temp water and counted the drops which equaled 20 drops exactly....then I took a duplicate dropper and did the same thing but with the juniper/PG solution....this was 40 drops exactly....the specific gravity made quite a difference.

Excellent experiment. :) - From memory it is surface tension that controls the size of the drops. Surface tension even in water changes with temperature.

Unregistered
10-21-2009, 03:17 AM
how many drops per aqueous solution and per oily solution
How many drops are in one milliliter?

Unregistered
11-08-2009, 12:29 PM
depends on the viscosity of the liquid.

Unregistered
12-10-2009, 04:11 AM
It's 20 drops per mL. I work in a pharmacy and that's the standardized conversion for any prescription or OTC medication (i.e. eye drops, ear drops, formularies, etc.) Or in other words, 1 drop = 0.05 mL

Unregistered
01-15-2010, 08:31 AM
How many drops are in one milliliter?

Unregistered
04-26-2010, 06:55 PM
Depends on how big your drops are. They tend to be between 15 and 25drops

phazei
05-24-2010, 11:55 PM
So, pushing aside all these 'standards'.

How many drops are in a milliliter, at STP (not stone temple pilots), of pure distilled water given it's specific viscosity/surface tension?

Unregistered
09-29-2010, 04:23 PM
Seriously! I just want to know how many drops in a milliliter!! I don't care about anything else. Get a life!!!

anyone1967
10-21-2010, 03:21 PM
OK, in Nursing and Medicine, there are 15 -16 drops in one milliliter. Hope that helps!

Unregistered
11-12-2010, 06:14 PM
Ok:

1. This question cannot accurately be answered. Some industries / scientists / etc. use different conventions to conveniently estimate the number of drops to ml's, those conventions are for conveniences sake only and are influenced by any number of factors.

2. Wikipedia is roughly as accurate as encyclopedia britannica according to studies. Don't believe me? Read it on CNET.

news.cnet.com/2100-1038_3-5997332.html

3. For the purposes of an OTC pharmaceutical estimate, basic measuring for non-life safety applications, you can be safe with the 20-drop/ml estimate. Dribble the substance at a constant rate of pressure so that it "naturally" drops away. Use an eyedropper with a semi standard style opening. Allow liquids to come to room temperature before dripping if greater precision is required.

4. If this level of detail is not good enough, get some functional training in chemistry. You're going to need it to mathematically determine the molecular weight per ml of mixtures. Once you have that and a serious scale you can measure to your hearts content. If you can't hang that, at least get a finely calibrated tiny graduated cylinder. Some of the tiny ones have subdivisions substantially less than 1ml. Make sure you measure from the Meniscus and good luck!

Ex Lux

chethanjungir
01-05-2011, 05:12 PM
how many drops of thioglycolic acid makes 1 millilitre

Unregistered
01-06-2011, 07:15 AM
Regarding medmath, there are 15 drops in a milliliter.

Unregistered
01-11-2011, 04:31 PM
How many drops are in one milliliter?

how many drops in one milliliter ?

Unregistered
03-10-2011, 10:24 AM
There are a number of variables to consider. Most importantly, I have not seen any responses in this thread that have inquired relative to the container and dispensing system. Additionally, viscosity of the solution being dispensed should be afforded consideration as well, as viscosity is dynamic...water even changes viscosity depending on temperature.

With that said, if this is an ophthalmic solution, most bottle and tip manufacturers will publish a drop size around 40ul (microliters) for their standard tip. However, the reported range for a drop dispensed is anywhere from 35-50ul. There are 1000ul:1mL. Therefore, if you assumed that each drop were 40ul, you would get approximately 25 drops per mL of solution. So, a standard 15mL boston round bottle containing a standard (non-gel) artificial tear, with a TRUE fill rate of 15mL, should produce close to 375 drops. Another thought...the eye only can hold 6-7 ul of fluid...so the real question: "Why such a large drop size?"...to be continued!

p.s. the eye produces about 0.5-2.2 ul of tears each minute...

Unregistered
03-14-2011, 06:24 PM
How many drops are in one milliliter?

Mrs X
03-15-2011, 11:27 AM
How many drops are in one milliliter?

Suggest you read the last 4 pages of posts, and pick a number. :D

Unregistered
03-29-2011, 01:58 PM
I counted 160 drops to fill a graduated cylinder to 10 ml with RO water. Therefore, my dropper dispenses 1 ml in 16 drops. The best way to know for sure with your liquid and your conditions is to count drops. The standard of 20 was WAY off in my application. I think the 20 drop standard could be more about building profits into drug prescriptions.

Unregistered
05-21-2011, 01:22 AM
In cooking, a drop is about 0.051 milliliter, specifically it is 1/96th of a teaspoon.

In pharmacies, a drop used to be another name for a minim, which would make it 0.0616 milliliters.

But now the drop is standardized in the metric system to equal exactly 0.05 milliliters.

Unregistered
06-13-2011, 05:12 AM
How many drops are in one milliliter?

Unregistered
07-28-2011, 09:39 AM
How many drops are in one milliliter?

How many drops in one milliliter of Liquid?

Unregistered
07-29-2011, 01:56 AM
How many drops are in one milliliter?

may be 10 drops

Unregistered
09-05-2011, 12:36 PM
How many drops in millimeter j

Robert Fogt
09-05-2011, 10:25 PM
How many drops in millimeter

A millimeter is a unit of distance not volume.

If you meant milliliter, there are 20 drops using the metric definition of 0.05 milliliters per drop.

Unregistered
10-28-2011, 03:01 AM
how many drops are in one milliliter? kindly quote the answer of how many drops in one millilitre

JohnS
10-28-2011, 03:58 AM
kindly quote the answer of how many drops in one millilitre

It's a variable. Depends on the dropper, liquid, temperature, etc.
Go back through thread and read in particular posts 2, 9, 22, 23, 40 and a few others. If the answer really matters, experiment with your dropper and your liquid. Otherwise, about 20 give or take, if viscosity is close to that of water.

georgejoan
11-02-2011, 10:48 AM
How many drops are there in 1 ml from a glass dropper

Tu J
11-19-2011, 12:25 PM
I'm a pharmacist and we use 20 drops/ml for calculating how many drops will be in a bottle of an eye drop we dispense. Insurance companies tend to use the same.

It's dependent on the type of medication and viscosity likely, but 20 is the standard answer.

Real life Example: 2.5ml bottle of Xalantan eye drop would have 50 drops. This given into each eye at bedtime would calculate to 25 days supply. If you send an electronic claim to the insurance for a lower day supply (ie. 10 days) it will reject. If you put 50 days supply, and the patient comes back at 25 days, then the next claim will reject (as a Refill too soon because you stated the bottle would last 50 days).

Unregistered
01-11-2012, 08:18 AM
Its 25 drops per ml, you guys are all wrong

you are in error, it is 20 drops/mm

Unregistered
02-03-2012, 08:12 AM
1 drop of human serum weighs ~ 0.1g

TomLovesGod

Unregistered
02-04-2012, 07:27 AM
It depends on viscosity also on the size of the pipette opening.

Unregistered
02-23-2012, 08:08 AM
There are certain condition that affect the volume of a droplet:
*temperature
*angle
*surface tension
*(viscousity,thickness etc.)what kind of liquid? Corn syrup or water?
So therefore there is no real answer for that question.

Unregistered
03-07-2012, 07:23 AM
Tell me about it. I am currently editing the Wikipedia article on drop (unit) and trying to figure out where some of the unreferenced material came from. That's what led me to this site. When you read something in the Wikipedia, check to see if there is a footnote and a reference, then check the reference to see if it's a) reliable, and b) says what the article claims it says.

Unregistered
05-09-2012, 01:21 AM
Wow, I hope none of you are medical!
Millilitre is Ml not mm
20 drops per Ml
This is based on standard infusion sets and is close enough for medications taking viscosity and temperature into consideration.

This is for yjr rest of the world. U.S.A. does their own system using a system devised sometime B.C.
A minim..something like that. You can buy minims using beads and sheckles

Unregistered
10-10-2012, 12:06 PM
I am working for my Ph.D in chemistry. Throughout my whole career as a student I have been told and have always used 20 drops = 1 mL. I would bet all the money I have that there are 20 drops in 1 mL. I have used a pipette for transfer 1 mL of a substance and it always comes out to around 20 drops. If that isn't proof enough, then go out and try it yourself. Also, the above posts do show accurate data.

Unregistered
11-10-2012, 02:59 PM
how many drops are there in 1ml liquid

Unregistered
02-05-2013, 02:46 AM
1ml is equal to 20 drops

Blazen
02-17-2013, 11:02 AM
JUST FOR GIGGLES!

Using medical syringes without a needle it took 15 drops of water to fill 1/8th teaspoon which is exactly what it should be. Then I attached a 27 gauge needle (0.01625 dia.) and did it again. It took 100 drops.

By luck, I had a pipette whose O.D. was nearly the same size as the I.D. of the syringes (about .0935) but its I.D. was .035. Since .035 is about twice the size of the needle I was expecting the drops it made to be about twice the size too but it didn't work that way. It took 15 drops to fill 1/8th tsp. just like the syringe without the needle did.

Baffled I watched very closely what was happening. Turns out that as it started to form a drop the water spread out to edges (O.D.) of the pipette and clung on to it. So despite the pipette having a very tiny hole it still made a normal (correct sized) drop because of the water clinging to the whole diameter of pipette which was the same size as the hole in syringe.

The O.D. of the syringes are slightly tapered so the water can't get to the outer edges while my pipette tip was a flat or squared off cut making that really easy.

I also noticed that different materials like glass versus metal or plastic made a difference in drop size as water clings to plastic better than it does to glass.

In case you were wondering... It only takes 5 drops from a turkey baster to fill 1/8th tsp!

JohnS
02-17-2013, 11:59 AM
Wow, I hope none of you are medical!
Millilitre is Ml not mm
20 drops per Ml
This is based on standard infusion sets and is close enough for medications taking viscosity and temperature into consideration.

This is for yjr rest of the world. U.S.A. does their own system using a system devised sometime B.C.
A minim..something like that. You can buy minims using beads and sheckles

Got to watch case in metric. A "Ml" is a megaliter, "ml" ("mL" in American) is milliliter. That 50000 L water drop sounds like a water bomber fighting a forest fire.

The US pharmaceutical industry is metric. Minims have gone out of style.

Unregistered
02-20-2013, 03:12 AM
Actually an ml will yield an average of 18 drops and it might vary due to kind of container, dispositive or instrument that is use to apply the drops. God bless.

Unregistered
04-05-2013, 07:59 AM
16 drops in 1ML

albert12
05-03-2013, 11:03 AM
There are about 20 drops of water in 1 milliliter. Eye drops are about the same. For other liquids, the number depends on the viscosity of the liquid, which affects the average drop size. Thicker, more viscous fluids are likely to produce larger drops and therefore fewer drops per milliliter. Note that 1 milliliter is equal to 1 cc.

Unregistered
05-24-2013, 09:10 AM
This is all very interesting -- I love the way the pharmacists all insist there are 20 drops per ml, it's just a pity they don't live in the real world!

I had a cataract operation on my right eye 19 days ago and I was provided with 5ml Levofloxacin (antibiotic) with instructions to use one drop in the eye four times a day for 7 days. No problem, there's plenty left.

I was also provided with 5ml Maxidex (corticosteroid suspension) which I was to use at the rate of one drop per eye four times a day for 28 days. According to you pharmacists, living in pharmacy-space or wherever it is you reside, that bottle was supposed to last me 28 days. According to your unbendable rule of thumb, it should have lasted 20x5/4=25 days -- 3 days short. According to reality -- me carefully squeezing a stiff, tiny plastic dropper bottle over my eye -- there's no more than two days worth left, a shortfall of 7 days and definitely more like 17 drops per ml than 20

Unregistered
05-24-2013, 02:26 PM
This is all very interesting -- I love the way the pharmacists all insist there are 20 drops per ml, it's just a pity they don't live in the real world!

I had a cataract operation on my right eye 19 days ago and I was provided with 5ml Levofloxacin (antibiotic) with instructions to use one drop in the eye four times a day for 7 days. No problem, there's plenty left.

I was also provided with 5ml Maxidex (corticosteroid suspension) which I was to use at the rate of one drop per eye four times a day for 28 days. According to you pharmacists, living in pharmacy-space or wherever it is you reside, that bottle was supposed to last me 28 days. According to your unbendable rule of thumb, it should have lasted 20x5/4=25 days -- 3 days short. According to reality -- me carefully squeezing a stiff, tiny plastic dropper bottle over my eye -- there's no more than two days worth left, a shortfall of 7 days and definitely more like 17 drops per ml than 20
I've just realised it's quite a bit worse than that -- is it like the Chinese water torture? Do some of these eye drops attack the brain and affect the memory? My eye op was in fact 16 days ago, not 19 as I initially stated. That means a shortfall of about 10 days and the equivalent of more like 14.4 drops per ml!

Mrs X
05-24-2013, 07:25 PM
I've just realised it's quite a bit worse than that -- is it like the Chinese water torture? Do some of these eye drops attack the brain and affect the memory? My eye op was in fact 16 days ago, not 19 as I initially stated. That means a shortfall of about 10 days and the equivalent of more like 14.4 drops per ml!

I don't understand why they make eye drop bottles SO difficult to get drops out of. - Hope you are happy with the operation otherwise.

I've got both a relative and a work colleague who have had cataract operations in the last month, and it seems the recovery care is quite important. It may be a good idea for you to have a chat to your Dr to just make sure he doesn't want to provide another prescription for the other half of the time. - I'm not a medical person, don't take this idea to heart if you have already been told something else by someone who knows. :)

Unregistered
05-30-2013, 08:26 AM
15-16 drops per 1 mL after several tries.
I just measured water drops in the lab using a high precision digital scale; 68F, DI water, dropper, Barometer 30.15inHg. This almost matches the Windows Convert program by Joshua F. Madison.

Unregistered
06-13-2013, 12:28 PM
How many drops are in one milliliter?

Unregistered
08-13-2013, 09:53 AM
in medical school I learnt that although the drop can change with the viscosity (or degree of molecule adherence), in general, in medical terms, a drop is a useful unit as when referred to a solution it does not change its volume thus allowing for a constant administration of a given dose of drug.
Now, in Europe (I'm from Italy, currently working in the UK), one ml = 20 drops. If you want to calculate how much medication is present in 5 drops, you need to know what it the actual concentration of the medication in 1ml. So let's say that your drug is 10mg/ml. If you were prescribed 5 drops once daily, then the computation would be pretty easy:
1 ml = 20drops
then, 10mg = 20drops = 1ml
now, 20:10=5:X
X=10x5/20
X= 2.5mg
you would be taking 2.5mg in 5 drops.

Unregistered
09-18-2013, 04:02 PM
Ha wikipedia is much more accurate than what you guys are talking about. 0.0616 minim/mL, so 1 mL = 16.2 drops. I would go with 20 drops/mL!

Unregistered
10-02-2013, 09:22 AM
The answer depends on the purpose behind the question in my humble opinion.

From a pharmacy audit standpoint the answer depends on which eye drop and possibly which insurance is being billed.

Typically between 15 and 20 drops per ml is used to calculate days supply. I have seen crazy variances and a chart at a pharmacy I once worked for.

The fail safe is 20 gtt/ml but this can cheat the patient or cause extra copays but it provides the greatest protection from audit and the insurance likes it since if it is over a 30days supply the patient copay is more aka= the insurance pays the pharmacy less. I have seen much higher and lower drops per ml. :-/

-PharmD, RPh.

Unregistered
10-14-2013, 02:05 PM
If looking at this from what the laws of physics give us, there is no definitive amount of drops in a mL as a standard unit. It all depends on the surface tension and density of the liquid being dripped, the dropper, and other more negligible factors; such as temperature, air pressure, and other environmental and atmospheric conditions like altitude. In any case, because of the vast range of densities for a multitude of liquids, with each having a different surface tension, all will produce a different size drop. This hold true even if a standard dropper was used under the same conditions.

Wulf
11-07-2013, 04:55 PM
According to the 22nd edition of the Drug Information Handbook, 1 minim is equal to 0.06 mL. And older version I was using today however rounded it down to 15 minim per mL.

Unregistered
11-20-2013, 03:46 PM
Its 25 drops per ml, you guys are all wrong

I think that's right thanks

Nguyen
11-24-2013, 09:38 AM
I am forever indebted to you for this innotmariof.