Drug Dosage Assignment

Math Skill:

Determining the dose to give to a client when the drug is labeled as a percentage solution.

Necessary Knowledge:

  1. 1 GRAM = 1000 MILLIGRAMS
    note: The whole problem must be stated in either grams or mg, not both.

  2. EVERY 1 PERCENT OF A SOLUTION CONTAINS 1 GRAM OF THE DRUG IN EVERY 100 mL OF THAT SOLUTION

examples:

  • 1% solution contains 1 gram of drug/ 100 mL
  • 5% solution contains 5 gram of drug/ 100 mL
  • 10% solution contains 10 grams of drug/ 100 mL
  • 0.1 % solution contains 0.1 gram of drug = 100 mg of drug/ 100 mL
  • 0.5 % solution contains 0.5 gram of drug = 500 mg of drug/ 100 mL
  1. THE FORMULA TO FIGURE A DOSE TO GIVE IS:

(DESIRE*STOCK)/HAVE = Amount to give client

DESIRE : the doctor's order
HAVE   : strength of the drug available on the nursing unit
STOCK  : form of the drug available on the nursing unit

Examples of stock:

1 tablet . . . . . . . . . the answer will be in tablets of halves of a table
1 mL ampule . . . . . . . . . the answer will be in parts of a mL.
Figure the answer to 2 decimal places
100 mL of solution . . . . . . . . . USED ANY TIME PERCENTAGE IS MENTIONED
the answer will be in mL

Sample question involving percentage solutions:

  1. How many mL of a 2% drug solution must be used to inject 30 mg of the drug?

Desire = 30 mg
Have = 2 grams = 2000 mg
Stock = the 2 Grams is in every 100 mL

(30*100)/2000  = Y

(3/2) = 1.5mL

Part 1:

Compute the answers to these questions and submit the answers to your teacher.

Student:

1. How many mL of a 10% drug solution must be used to inject 1 gram of the drug?
2. How many mL of a 1% drug solution must be used to inject 5 mg of the drug?
3. How many mL of a 0.5 % drug solution must be used to inject 2.5 mg of the drug?
4. How many mL of a 1% drug solution must be used to inject 5 mg of the drug?
5. How many mL of a 40 % drug solution must be used to inject 0.08 mg of the drug?

 Part 2:

Make up two problems like those above, and use the formula to solve them. Show how you placed the information in the formula, and show your math.

Problem #1:

 

Problem #2:

 

 

 

Grading critera for this task:

GRADING CRITERIA for this task emphasize the necessity of being correct consistently when computing medication dosages.

GRADING FOR PART I:

5 correct answers = 50% 3 correct = 25% 2 correct = 0%

GRADING FOR PART II:

Both examples are fully worded as nursing medication orders = 20%
Only one example is fully worded = 10%

Both examples show how the numbers are fit into the formula = 15%
Only one example does this = 5%

Both answers are correct = 15%
Only one answer is correct = 5%