Aprovider order states, “meperidine (demerol®) 45 mg, atropine sulfate (atropine®) 0.3 mg im now.” the meperidine (demerol®) comes in a pre-filled syringe containing 50 mg/ml, and the atropine sulfate (atropine®) comes in a vial containing 400 mcg/ml. what is the total volume that the nurse will be injecting?

To find the volume, just divide the mass by the dosage in mass per volume. Then, add both volumes to find the total volume. The solution is as follows:

45 mg ÷ 50 mg/mL = 0.9 mL

For the second unit, mcg is micrograms. For every 1 mcg, there is 0.001 mg. Thus,

400 mcg/ml * 0.001 mg/1 mcg = 0.4 mg/mL
0.3 mg ÷ 0.4 mg/mL = 0.75  mL

Total Volume = 0.9 mL + 0. 75 mL = 1.65 mL