A morphine 4 mg IV dose is prescribed for a myocardial infarction. If morphine is 10 mg/mL, how many milliliters should be administered?

A morphine 4 mg IV dose is prescribed for a myocardial infarction. If morphine is 10 mg/mL, how many milliliters should be administered?

• A. 0.2 mL
• B. 0.4 mL
• C. 0.6 mL
• D. 0.8 mL

Answer: (B)

When you need to convert a prescribed dose into a volume, use volume = dose ÷ concentration. The morphine solution provides 10 mg in every 1 mL, so to deliver 4 mg, you calculate 4 mg ÷ 10 mg/mL = 0.4 mL. Therefore, administer 0.4 mL. A smaller volume (0.2 mL) would give 2 mg, a larger one (0.6 mL) would give 6 mg, and 0.8 mL would give 8 mg.

When you need to convert a prescribed dose into a volume, use volume = dose ÷ concentration. The morphine solution provides 10 mg in every 1 mL, so to deliver 4 mg, you calculate 4 mg ÷ 10 mg/mL = 0.4 mL. Therefore, administer 0.4 mL. A smaller volume (0.2 mL) would give 2 mg, a larger one (0.6 mL) would give 6 mg, and 0.8 mL would give 8 mg.