Transcript Calculating Medication Dosages

Calculating Medication Dosages
Three Steps
1. Verify the drug available is the same
measurement system as the drug dosage desired
(convert if needed)
2. Reduce to lowest terms.
3. Calculate dosage quantity to be administered
Slide 1
Drug Calculation Methods
 Fraction Method
 600 mg = 200 mg
x tablets
1 tablet
Solve for x
Slide 2
Drug Calculation Methods (cont.)
 Desired over Available Method
Desired units (Conversion factor) x
Quantity of drug form = Quantity to give
Quantity available (x conversion factor)
Doctor’s order X quantity = ?
On hand
Slide 3
Forms of Oral Medications
 Capsules
 Cannot be broken or divided
 If amount to be given is more than 0.5, round to next
whole number
 Tablets
 Only divide if scored
 Coated tablets are not to be broken
 Liquids
 May be measured in a medication cup, syringe, or
calibrated dropper
Slide 4
Parenteral Medications
 Medication available in three forms:
 Prefilled syringe labeled with specific dosage
 E.g., meperidine (Demerol) 100 mg in 1 mL
 Single or multiple-dose ampule or vial labeled with a
specific dosage per volume
 E.g., epinephrine (Adrenalin) 1:1000 in 0.1 mL
 A vial with powder that requires a specific fluid to be
added to it to obtain a specific dosage (Reconstitution)
Slide 6
Insulin
 A critical medication that replaces the insulin
not being produced by the patient’s pancreas
 Insulin comes in a standardized measure
called a “Unit”
 Smallest amounts may be given; errors are
critical
Slide 7
Insulin (cont.)
 Strengths
 U-100 (100 Units of insulin per 1 mL)
 Syringe
 Calibrated in Units also
Slide 8