You are preparing to administer 40 mg of a medication supplied as 10 mg/mL. Using dimensional analysis; how many should you administer?

• Convert the prescribed dose to mg

0.75 g = 750 mg

• Identify the available tablet strength

Available Tablet Strength: 250 mg/tablet

• Calculate the number of tablets

Number of Tablets = Prescribed Dose ÷ Tablet Strength

Number of Tablets = 750 ÷ 250

Number of Tablets = 3 tablets

A. A tuberculin syringe calibrated in milliliters: Tuberculin syringes are calibrated in milliliters, not insulin units. Using them for insulin increases the risk of dose miscalculation and medication errors, especially with high-alert drugs like insulin.

B. A U-100 insulin syringe calibrated for up to 50 units: A U-100 insulin syringe is specifically designed to measure U-100 insulin accurately. A syringe calibrated up to 50 units allows precise dosing without excess space, reducing the risk of dosing errors.

C. A U-500 insulin syringe calibrated for 500 units: U-500 syringes are intended only for highly concentrated insulin. Using this syringe for U-100 insulin would result in a major dosing error and potential severe hypoglycemia.

D. A 1-mL syringe calibrated in milliliters: Although a 1-mL syringe can physically hold the volume, it is not calibrated in insulin units. This makes accurate insulin measurement difficult and unsafe compared with a dedicated insulin syringe.