Med Dosage Calculation

Common Conversion Used in Nursing

1ml = 1cc = 15gtt
1ml = 60 microdrops
1t = 5ml
1T = 3t = 15ml
1 oz = 30ml
1cup = 240ml
1L = 1000ml
1ml = 15 minims
1g = 1000mg = 1000mcg
1kg = 2.2 lbs
1 grain = 60mg *grain is always expressed in Roman Numerals

Click below to see a sample computation and sample problems

Sample problem:

MD ordered Aspirin gr X for headache. The drug on hand is Aspirin 300mg. What would be the correct dosage?
*always write the unknown on the left side and start your solution on the right that corresponds to the given*

solution:

Tab = 1tab x 60mg x 60gr = 2tablets
_____________________
..... 300mg .... 1gr
* cross out the same units of measurements (like those in red) and you will be left with whatever you were looking for*



SAMPLE MATH TEST:
1. A client has an order for Chloromycetin 500mg q6 hours. The drug comes in 250mg per capsule. How many capsules would the client receieve in 24 hours?

2. A client has an order for Phenobarbital gr. 1.5 The drug is available in 30mg tablets. What would be the correct dosage?

3. An order of Aminophylline 300mg IV STAT was ordered. The stock is 200mg/5ml. How much of this drug should the patient get?

4. A client has an order for Ampicillin 500m. The stock is Ampicillin 125 mg. How many capsules should the patient get?

5. The doctor has ordered Toradol 45mg IM for migraine headache. The medication is supplied in 30mg/ml. How many ml should the nurse give?

6. The physician has ordered Lovenox 80mg SQ QD for prevention of DVT. The medication comes in 80mg/0.8ml. How many cc should the nurse administer?

7. A patient's meal tray came back with the following items consumed. 1 cup of coffee, 1/2 cup of milk, 2 cups of fruit juice, 1 cup of jello. What would be documented in the patient's intake?

8. The doctor Ordered Stadol 0.002g IM PRN for pain. The drug is supplied in 1mg/ml. How many mililiters will the nurse administer?


Answer:
1. 2 capsules
2. 3 tablets
3. 7.5 ml
4. 4 capsules
5. 1.5 ml
6. 0.8 ml
7. 840 oz
8. 2 ml