This document provides instructions and examples for calculating dosages of medication when the prescribed dose differs from the available form. It explains that proportions should be set up and cross-multiplied to determine the amount needed. Several examples are provided of calculating required tablets, milliliters, or other units using proportional reasoning from the prescribed dose and available concentration. The objective is to practice mathematical skills for determining correct medication dosages.

1. Dosage Calculations January 10, 2013
Warm Up
4 kg = _____ g
.45 mg = _____g
Objective: Using math for medicine.
Jan 5­1:36 PM
HW Prescribed Dose Worksheet 1

2. Dosage Calculations January 10, 2013
Jan 4­11:31 AM
HW Prescribed Dose Worksheet 2

3. Dosage Calculations January 10, 2013
Medication may be ordered in a form or amount different from what is available.
Use proportions to calulate the right dosage.
Steps:
a. Set up proportion
b. Check to be sure units are the same horizontally
c. Cross multiply and solve for x.
Jan 5­2:03 PM
HW Prescribed Dose Worksheet 3

4. Dosage Calculations January 10, 2013
Example 1:
60 mg of medication are ordered. Tablets are available which have 30 mg
of medication in each of them. How many tablets are needed to give 60 mg?
a) Set up as a proportion:
b) Are your units the same horizontally?
c) Cross multiply and solve.
Jan 5­2:05 PM
HW Prescribed Dose Worksheet 4

5. Dosage Calculations January 10, 2013
Ordered: 15 mEq
Available: 10 mEq/5cc
How many cc's needed?
Jan 5­2:10 PM
HW Prescribed Dose Worksheet 5

6. Dosage Calculations January 10, 2013
Ordered: gr 1
800
Available: gr 1 per ml
200
How many ml?
Jan 5­2:12 PM
HW Prescribed Dose Worksheet 6

7. Dosage Calculations January 10, 2013
Ordered: 40 units
Available: 100 units/ml
How many ml's should be given?
Ordered: 3 mg
Available: 1.5 mg/tables
How many tablets should be given?
Jan 5­1:39 PM
HW Prescribed Dose Worksheet 7

8. Dosage Calculations January 10, 2013
Jan 10­11:19 AM
HW Prescribed Dose Worksheet 8