Order: diphenhydramine 25 mg PO q6h, PRN

Available: diphenhydramine 12.5 mg/5 mL.

How many mL would the nurse give?

A) 600 g
This is incorrect because it represents the quantity 600 grams, which is a significantly larger amount than "six hundredth." The phrase "six hundredth" refers to six out of 100, or 0.06 in decimal form. In the metric system, 600 grams would indicate a much higher quantity, far from what is requested. Therefore, this option does not fit the definition of "six hundredth."

B) 0.06 g
The term "six hundredth" refers to six parts out of one hundred, which is mathematically expressed as 0.06. In the metric system, it is common to represent small quantities of mass, such as grams, in decimal form. The number 0.06 is precisely six hundredths, and the proper representation for this in terms of grams is 0.06 g. This is the correct scientific notation for the given quantity, as it accurately reflects six hundredths of a gram.

C) 0.006 g
This is incorrect because 0.006 grams represents six thousandths, not six hundredths. In decimal notation, six thousandths would be represented as 0.006, which is one order of magnitude smaller than six hundredths. The difference between 0.006 and 0.06 is significant. While both numbers are small, 0.006 would refer to an even smaller quantity than 0.06, which is not in line with the intended meaning of "six hundredth."

D) 0.6 g
While 0.6 grams may appear similar at first glance, it represents six-tenths (6/10), not six hundredths (6/100). The number 0.6 is much larger than 0.06, and it would be used to indicate a weight that is 60% of a gram, not a small fraction like six hundredths.

Identify the desired dose and the available concentration:

Desired dose: 5 mg of hydrocodone

Available concentration: 7.5 mg of hydrocodone in 15 mL of elixir

Calculate the volume needed for the desired dose using the formula:

Volume(mL)=(Desireddose(mg)/Availableconcentration(mg/mL))

Determine the available concentration in mg/mL:

Availableconcentration=(7.5mg/15mL)=0.5mg/mL

Calculate the volume needed for a 5 mg dose:

Volume(mL)=(5mg/0.5mg/mL)=10mL