dosage calculation (pharm)

yes. ratios will work when you need to covert from one measurement to another. you employ a ratio that is really an equivalent expression so that the numerator is equavalent to the denominator. you do this to cancel out labels on the numbers in your equations you set up. this is the dimensional analysis way to work problems and works particularly well where you have to determine iv drip rates.

the formula for calculating drug dosages that i have been using for 30 years in my jobs as a hospital nurse is:

this formula will work for most medication problems including iv solutions that have medication in them where you have to determine how many cc/s or ml/s of the solution to give over an hour period of time.

please look through my recent postings on math questions as i gave a rather extensive post with web links for help with math calculations. do you know how to find a list of other members postings? i regularly check nursing student assistance forum, general nursing student discussion forum, and the pre-nursing student discussion forum looking for those asking for help with math, chemistry and anatomy. these two sites bear repeating:

http://www-isu.indstate.edu/mary/tutorial.htm - from the indiana state university a "basics" page on medication math with explanations on how to do a number of different types of medications problems (including iv problems), conversions and dimensional analysis with links to lots of practice quizzes.

http://www.accd.edu/sac/nursing/math/mathindex2.html - basic tutorial on getting started with pharmacology math. at the bottom of this home page is a drop down box where you link into any of the following subjects: common conversion factors/equivalencies, common abbreviations, ratio and proportion, iv problems, titration problems, and pediatric pharmacology math.

http://www.accd.edu/sac/nursing/math/default.html -- the start page of this pharmacology math tutorial presented by the nursing department at the san antonio college. by clicking on the "go figure" button you can access quizzes on basic med calculations, iv, pediatric and ob med calculations. the quizzes all have answers. follow the directions.

you have to work problems over and over to "get" how to set them up. when you get the right answer, you should take the entire equation and practice with it by removing one of the other elements within it and forming a new problem. do this over and over with the practice problems you are working. hint for working with word problems: with most word problems you always want to look at the very last sentence. that is usually where the problem tells you what it is asking you to find. then, you will find the pieces you need to set up the math to get that answer from the information given before that last sentence. sometimes you will be given extra extraneous information. you need to be confident enough in working problems to realize when you are being given useless information that is nothing more than a red herring to see if you know what you are doing.