Ordered: Clozaril 75 mg bid for 4 days

On hand: See label

What is the amount to dispense?

1: This is a medication cup, which is not suitable for measuring a small volume like ¼ teaspoon with a high degree of accuracy. Its large capacity and wide rim make it prone to measurement errors for such a small dose. Additionally, its shape is inappropriate for instilling medication into an ear.

2: This is an oral syringe, which is a good device for accurately measuring small liquid volumes. However, its primary design is for oral administration. While it could be used for instillation, the dropper is more suitable for this order.

3: This is a medication dosing spoon or oral dispenser. While it has markings for fractions of a teaspoon, it is designed for oral administration. Its shape would make it difficult to precisely and safely instill medication into an ear, as the liquid would likely spill.

4: This device is a dropper, which is the most appropriate tool for this medication order. It has clear markings for a quarter-teaspoon, allowing for accurate measurement of the small dose. A dropper is also specifically designed for the ordered route of administration, "instilled into the right ear," enabling the precise and safe delivery of the medication.

Desired dose = 135 mcg.

• Convert the desired dose from micrograms (mcg) to milligrams (mg) to match the available concentration's unit.

Since 1 mg = 1000 mcg,

Desired dose in mg = 135 mcg / 1000 mcg/mg

= 0.135 mg.

Available concentration = 0.25 mg/mL.

• Calculate the volume to administer.

Volume (mL) = Desired dose (mg) / Available concentration (mg/mL)

= 0.135 mg / 0.25 mg/mL

= 0.54 mL.