A nurse is preparing to administer lithium 300 mg PO to a client who has bipolar disorder. Available is lithium 150 mg capsules. How many capsules should the nurse administer? (Round the answer to the nearest whole number. Use a leading zero if it applies. Do not use a trailing zero.)

Let's calculate the dosage using the provided information.

Information from the label:

Bumetanide concentration: 0.25 mg/mL

Available volume: 10 mL vial

Order: Bumex (bumetanide) 1 mg IV daily

Calculation:

Determine the desired dose: 1 mg

Use the formula:

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

Substitute the values:

1 mg / 0.25 mg/mL = Volume to administer (mL)

Calculate:

Volume to administer = 4 mL

Therefore, the correct answer is C. 4 mL

A) 0.2 mg
The correct way to write the dosage is 0.2 mg. In pharmacology and medication administration, it is important to follow the guidelines set by the Institute for Safe Medication Practices (ISMP) and other standard bodies, which recommend that a leading zero be used before a decimal point. This helps to prevent errors in interpreting the dosage. Writing 0.2 mg clearly indicates two-tenths of a milligram, and the leading zero makes it easier to avoid misreading the dose as a whole number (2.0 mg) or omitting the decimal point entirely.

B) .2 mg
Writing the dosage as .2 mg (without the leading zero) is considered unsafe and is a poor practice. The absence of the leading zero before the decimal point increases the likelihood that the dose may be misread. For example, someone could confuse .2 mg with 2.0 mg or misinterpret it in a hurried situation, which could lead to a tenfold dosing error

C) 2.0 mg
Writing 2.0 mg would indicate two milligrams, which is not the correct dosage for "two-tenths of a milligram." While this format does use a decimal point, it does not represent the correct dose. This error could lead to an overdose if misread as a whole number.

D) 0.20 mg
While 0.20 mg is technically correct, it is not the preferred or necessary format. The use of two decimal places is unnecessary in this case. Since the dosage is two-tenths of a milligram, 0.2 mg is simpler and clearer. Using an unnecessary trailing zero (the second "0") can cause confusion or misinterpretation, especially in critical settings where every detail counts.