A nurse is preparing to administer diphenhydramine 50 mg PO every 6 hr to a client who has acute dystonia. The available medication is diphenhydramine 25 mg tablets.

How many tablets should the nurse administer per dose?

Step 1: Identify the required dose of lithium, which is 300 mg.

Step 2: Identify the available dose of lithium carbonate, which is 150 mg per capsule.

Step 3: Calculate the number of capsules needed using the formula: Number of capsules = Required dose ÷ Available dose.

Numberofcapsules=300 mg150 mg/capsule

\(Number\ of\ capsules = {300\ mg \over 150\ mg/capsule}\)

Step 4: Solve the equation.

Numberofcapsules=2 capsulesNumberofcapsules=2capsules

So, the nurse should administer 2 capsules per dose to achieve the required lithium dose of 300 mg.

Choice A rationale:

The client’s reported behavior of using laxatives and inducing vomiting after eating can lead to a condition known as hypomagnesemia. Hypomagnesemia is a condition characterized by low levels of magnesium in the blood. This condition can be caused by poor intake, excessive loss, or movement of magnesium from the blood into less accessible locations. The use of laxatives can lead to excessive loss of magnesium through increased bowel movements. Similarly, self-induced vomiting can also result in a loss of magnesium. Therefore, the client’s behavior puts them at risk for developing hypomagnesemia.

Choice B rationale:

Renal failure, also known as kidney failure, occurs when the kidneys lose their ability to filter waste products from the blood. While the use of laxatives and self-induced vomiting can lead to dehydration, which can strain the kidneys, these behaviors are not directly associated with renal failure. Therefore, while it’s possible for the client to develop kidney problems, it’s less likely compared to hypomagnesemia.

Choice C rationale:

Heart failure occurs when the heart muscle doesn’t pump blood as well as it should. This condition can cause symptoms like shortness of breath, swelling, fatigue, and other symptoms. While severe electrolyte imbalances, such as those that might result from the use of laxatives and self-induced vomiting, can affect heart function, they would typically result in arrhythmias (irregular heartbeats) rather than heart failure. Therefore, it’s less likely for the client to develop heart failure based on the behaviors described.

Choice D rationale:

Hyperthyroidism is a condition where the thyroid gland produces and releases too much thyroid hormone. This condition can cause symptoms like rapid heartbeat, weight loss, and anxiety. The client’s behaviors of using laxatives and inducing vomiting after eating do not directly influence the production of thyroid hormones. Therefore, it’s less likely for the client to develop hyperthyroidism based on the behaviors described.