Correct Answer: B

Rationale: The correct instruction for the nurse to include in the teaching plan is to advise the client to avoid consuming grapefruit juice. Grapefruit juice can increase the risk of atorvastatin (Lipitor) toxicity by inhibiting its metabolism. Atorvastatin is typically taken in the evening as cholesterol synthesis occurs at night. Increasing dairy intake is not specifically recommended for atorvastatin therapy, and the medication can be taken with or without food.

Correct Answer: D

Rationale: Signs of toxicity related to oxybutynin chloride (Ditropan XL) include central nervous system excitation, such as nervousness, restlessness, hallucinations, and irritability. Other signs of toxicity may include hypotension or hypertension, confusion, tachycardia, a flushed or red face, and signs of respiratory depression. Restlessness is a sign of central nervous system excitation, which can indicate a possible toxic effect of this medication.

Correct Answer: B

Rationale: Sodium polystyrene sulfonate, such as Kayexalate, is a cation exchange resin that functions by releasing sodium ions in exchange for primarily potassium ions. This medication is commonly used to treat hyperkalemia, a condition characterized by elevated levels of potassium in the blood.

Correct Answer: B

Rationale: Atenolol hydrochloride is a beta-blocker used to treat hypertension. Checking the client's blood pressure is crucial before administration.

Correct Answer: D

Rationale: Iron absorption is enhanced by the presence of vitamin C. Orange juice is a good source of vitamin C, which can improve the absorption of iron when taken together. Therefore, administering iron supplements with orange juice is the best choice to optimize iron absorption for the child.