Medication calculations

Medication calculations
There are 4 basic steps to solving proportion problems:
1) Set up a known ratio.
2) Set up a proportion with known and desired units. Use x for the quantity that is
desired or unknown.
3) Cross multiply.
4) Solve for x.
Example:
Dose Ordered: Medication B 15 mEq po every day.
Available: Medication B 10 mEq/5ml.
How many ml’s will you give?
a) Set up proportion. (Units are matched therefore no need to convert- mEq to mEq and
ml to ml)
b) Cross multiply and solve for x.
10𝑚𝐸𝑞
5𝑚𝑙 = 15𝑚𝐸𝑞
𝑋𝑚𝑙
10x=75 x= 75
10 15 mEq= 7.5 ml
Calculating IV Flow Rates:
To find hourly rate (stated in mls per hour)
Total volume of solution in ml’s = x ml’s
Total amount of time in hours
Example: 1000 cc IV solution ordered to infuse over 8 hours.
1000 ml = 125
8 hrs.
Answer: 125 ml/hour
Example: 1000 ml solution to infuse over 6 hours