Unit 44

Calculating Oral Dosage

Interpreting Drug Labels

• Health care professionals must use extreme caution while preparing medications ordered by a physician.

• Correct interpretation of drug labels is essential.

Interpreting Drug Labels

• Information shown on the label includes:– Drug name– Dosage or strength with a unit of measurement– Manufacturer name – Quantity of medication the container holds– Special instructions for care– National Drug Code (NDC), which is a universal Food

and Drug Administration (FDA) product identifier for human drugs

Interpreting Drug Labels

• Health care professionals must read the label carefully before administering any medication.

• It is essential to check the name of the drug, the dosage per unit, and any special precautions that must be followed.

Basic Principles of Calculating Oral Dosage

• An oral medication is a medication taken by mouth. It is the most common route for administration of medications.

• Oral medications are available in solid forms such as tablets, capsules, powders, and lozenges, or liquid forms such as solutions, elixirs, suspensions, and syrups.

Proportional Method of Calculating Oral Dosage

• To use the proportional method, all units of measurement must be the same.

• When the units of measurement are the same, a proportion is created to represent the information:

Formula Method of Calculating Oral Dosage

• To use the formula method, all units of measurement must be the same.

• Numbers are then inserted into the formula to find the correct amount of medication:

Calculating Oral Liquid Dosages

• To calculate oral liquid amounts, the same procedures are used, but the liquid amount is used in place of the capsule.

Calculating Oral Dosage• Example: A doctor orders 300 milligrams (mg) of

Terramycin suspension, an antibiotic. The dosage available contains 0.1 g per 5 milliliters (mL).– Known fact: 1 g = 1,000 mg– Therefore 0.1 g = 100 mg– Use the formula:

Calculating Oral Dosage

– Set up a proportion:

100 mg x X mL = 5 mL x 300 mg

100X = 1,500

X = 15– The correct dose is 15 mL.

Practical Problem• A physician orders Klonopin 1 mg for a patient

with hypertension (high blood pressure).

• How many tablets should be given?

Practical Problem

• Create a proportion and solve:

• The patient should be given 2 tablets of Klonopin.