The nurse is explaining the differences between uncontrolled and controlled substances.
Which of the following medications is a controlled substance?

Choice A rationale

Losartan is an angiotensin II receptor blocker (ARB) that helps lower blood pressure by relaxing blood vessels. It is often prescribed for clients who cannot tolerate angiotensin-converting enzyme (ACE) inhibitors like Captopril or Lisinopril due to side effects such as a persistent cough.

Choice B rationale

Digoxin is a medication primarily used to treat heart failure and atrial fibrillation. It is not typically prescribed for the management of hypertension as it does not directly lower blood pressure.

Choice C rationale

Captopril is an ACE inhibitor that can cause a persistent cough in some patients. Since the client has experienced this side effect, it is unlikely that Captopril would be prescribed again.

Choice D rationale

Lisinopril is another ACE inhibitor, similar to Captopril. Given the client's history of a cough caused by ACE inhibitors, Lisinopril is also not a suitable option.

Choice A rationale

Dantrolene is used to treat malignant hyperthermia, a rare life-threatening condition usually triggered by certain anesthetics or muscle relaxants.

Choice B rationale

Although dantrolene is used to treat muscle spasticity, the indication in this question is specifically about malignant hyperthermia, making this choice not the most appropriate.

Choice C rationale

Dantrolene is not typically used for general pain management. Its primary use is in malignant hyperthermia and severe spasticity.

Choice D rationale

While reducing muscle stiffness can be a result of its spasticity treatment, malignant hyperthermia is a more specific and critical use of dantrolene.