Dosage Calculations-Formulas

Created by jpon 

Upgrade to
remove ads

D/H X Q

Dose divided by strength times quantity (ml or tablets)

Ratio and Proportion

1a. Supply over volume or amount
b. Volume or amount over X
2. Cross multiply
3. Divide the sides by X (value)
X = ?

Body Weight Dosing

mg X kg = patient dose (convert lbs to kg) 1kg = 2.2lbs
(divide total lbs. by 2.2kg to convert)
Example: 195/2.2 =88.6kg (be exact, round)
20mg X 88.6kg =1772mg (24 hour dose)
To figure # of doses in a day: Q12=2, Q8=3, Q6=4, Q4=6

Clark's Rule: means of calculating a child dose of medication from an adult dose on the basis of the child's weight in pounds.

child's weight in pounds divided by 150 (adult average weight)
times usual adult dose=child's dose (D/H X Q)
Example: 40/150 = 0.26 X UAD = Child's Dose

Young's Rule: means of calculating a child dose of medication on the basis of the child's age.

Age in Years divided by Age in Years plus 12 X Adult Dose = Child's Dose (example: 6/18= 0.33 X 500mg = 165mg)

Fried's Rule: means of calculating an infant dose of medication from an adult dose on the basis of the infant's age in months. (use with children up to one year)

Age in months divided by 150 (average adult weight) X Adult Dose = Child's Dose (example: 12/150 = 0.08 X 500mg = 40mg)

Please allow access to your computer’s microphone to use Voice Recording.

Having trouble? Click here for help.

We can’t access your microphone!

Click the icon above to update your browser permissions above and try again

Example:

Reload the page to try again!

Reload

Press Cmd-0 to reset your zoom

Press Ctrl-0 to reset your zoom

It looks like your browser might be zoomed in or out. Your browser needs to be zoomed to a normal size to record audio.

Please upgrade Flash or install Chrome
to use Voice Recording.

For more help, see our troubleshooting page.

Your microphone is muted

For help fixing this issue, see this FAQ.

Star this term

You can study starred terms together

NEW! Voice Recording

Create Set