A client is admitted for acute renal failure and the nurse is monitoring their response to medications. Which pharmacokinetic principle does the nurse understand will be affected in this patient?

Choice A reason: This statement is true. The nurse should instruct the client to avoid getting up without assistance, as hydralazine can cause orthostatic hypotension, which is a sudden drop in blood pressure when changing positions. This can lead to dizziness, fainting, or falls.

Choice B reason: This statement is false. The nurse should not tell the client that upper arm pain is common with this medication, as hydralazine does not cause this side effect. Upper arm pain may be a sign of angina, which is chest pain caused by reduced blood flow to the heart. The nurse should advise the client to report any chest or arm pain to the prescriber.

Choice C reason: This statement is false. The nurse should not tell the client to not alter the medication with birth control, as hydralazine does not have a significant interaction with hormonal contraceptives. However, the nurse should advise the client to inform the prescriber if they are pregnant or planning to conceive, as hydralazine may have some effects on the fetus.

Choice D reason: This statement is false. The nurse should not tell the client to immediately report a dry cough, as hydralazine does not cause this side effect. A dry cough is more common with angiotensin-converting enzyme (ACE) inhibitors, which are another class of antihypertensive drugs.

Choice A reason: This statement is true. The nurse should include this information with calcium channel blockers, which are a type of medication that relax the blood vessels and lower the blood pressure. Grapefruit juice can interfere with the metabolism of calcium channel blockers and increase their levels in the blood. This can cause serious side effects, such as low blood pressure, slow heart rate, or liver damage.

Choice B reason: This statement is false. The nurse should not include this information with calcium channel blockers, as checking the apical heart rate is not necessary before taking this medication. Calcium channel blockers can lower the heart rate, but not to a dangerous level. However, the nurse should monitor the client's vital signs regularly and report any abnormal findings.

Choice C reason: This statement is false. The nurse should not include this information with calcium channel blockers, as these medications are not used to reduce cholesterol. Calcium channel blockers have no effect on the cholesterol levels in the blood. However, the nurse should advise the client to follow a healthy diet and lifestyle to prevent cardiovascular diseases.

Choice D reason: This statement is false. The nurse should not include this information with calcium channel blockers, as these medications do not cause increased blood pressure. Calcium channel blockers lower the blood pressure by relaxing the blood vessels. However, the nurse should inform the client that some calcium channel blockers can cause headaches, flushing, or swelling of the ankles, which are mild and temporary side effects.