A medication order requires the nurse to administer 1.5 g of a drug. The supply is 500 mg per capsule. How many capsules should the nurse administer using dimensional analysis?

A. 2 capsules: Administering 2 capsules would only provide 1000 mg of the medication, which is 500 mg short of the prescribed dose. This sub-therapeutic dosing would fail to achieve the required plasma concentration for efficacy. It represents an incorrect application of dimensional analysis. B. 4 capsules: Delivering 4 capsules would result in a total dose of 2000 mg, which is a significant overdose. Excessive dosing increases the risk of pharmacological toxicity and adverse drug reactions. This calculation error violates the fundamental "five rights" of medication administration. C. 3 capsules: Using dimensional analysis, 1.5 g is converted to 1500 mg; dividing 1500 mg by the 500 mg strength per capsule equals exactly 3. This ensures the patient receives the precise dosage ordered by the provider. It is the correct mathematical result for this conversion. D. 5 capsules: A dose of 5 capsules would provide 2500 mg, which is nearly double the required 1.5 g amount. Such a large discrepancy in dosing could lead to severe patient harm or legal ramifications for the nurse. It indicates a failure to properly convert grams to milligrams.