A client has been prescribed an oral drug that is known to have a high first-pass effect. Which measure has the potential to increase the amount of the free drug that is available to body cells?

A. Changing positions slowly is critical for older adults taking beta-adrenergic blockers and diuretics to prevent orthostatic hypotension, which can lead to lightheadedness or dizziness.

B. Reducing fluid intake is not advisable, as thiazide diuretics can lead to dehydration, and maintaining adequate fluid intake is essential for overall health and to avoid excessive urinary output.

C. Identifying and eliminating high-potassium foods is unnecessary unless there is a specific indication of hyperkalemia, particularly since thiazide diuretics do not typically cause potassium retention, and beta-blockers are not potassium-specific.

D. Expecting blood pressure to increase before it decreases is misleading; clients should see a gradual reduction in blood pressure with proper medication adherence, and any sudden increases should be reported.

A. Chest pain and pale skin are not typical adverse effects associated with diltiazem use.

B. Shortness of breath and wheezing may occur due to other conditions or medications but are not common adverse effects of diltiazem.

C. Calcium channel blockers like diltiazem can cause peripheral edema due to vasodilation and bradycardia as a result of their action on the heart rate. Monitoring for these effects is essential in patients taking diltiazem.

D. Tachycardia is not an expected adverse effect of diltiazem; in fact, it is used to manage conditions where tachycardia may be present. Anxiety is also not a direct adverse effect of this medication.