mbination of two renin-angiotensin-aldosterone system (RAAS) inhibitors, such as angiotensin-converting enzyme inhibitors (ACE inhibitors) and angiotensin II receptor antagonists (ARBs) do not obtain any additional benefit compared to monotherapy. In general, avoid combined use of these drugs together. Closely monitor blood pressure, renal function, and electrolytes. Combination therapy has been associated with an increased risk of diarrhea, hypotension, syncope, hyperkalemia, and renal dysfunction resulting in dialysis, doubling of serum creatinine, and death. In the Ongoing Telmisartan Alone and in Combination with Ramipril Global Endpoint Trial (ONTARGET), the combination of ramipril 10 mg/day and telmisartan 80 mg/day did not provide a significant benefit in the prevention of death from cardiovascular causes, myocardial infarction, stroke, or hospitalization for heart failure compared to ramipril alone. There was, however, a significantly increased rate of renal dysfunction associated with combination therapy (13.5%) compared to ramipril (10.2%) or telmisartan (10.6%) alone and a significantly increased rate of hyperkalemia with combination therapy compared to ramipril (5.6% vs. 3.3%; p<0.001). Additionally, there was a significantly higher number of patients who discontinued therapy due to adverse reactions, including hypotensive symptoms (4.8% vs. 1.7%; p<0.001), syncope (0.3% vs. 0.2%; p=0.03), diarrhea (0.5% vs. 0.1%; p<0.001), and renal impairment (1.1% vs. 0.7%; p<0.001), from combination therapy compared to ramipril alone. In a separate analysis of the ONTARGET renal outcomes, the rate of the composite primary renal outcome of dialysis, doubling of serum creatinine, and death was similar with ramipril and telmisartan alone (13.5% vs. 13.6%, respectively), but was significantly higher with combination therapy (14.5%) compared to ramipril (p=0.037). In the CHARM-Added program, the combination of candesartan and an ACE-inhibitor resulted in an increased incidence of hypotension (22.6% vs. 13.8%), renal dysfunction (15% vs. 9%), and hyperkalemia (9.5% vs. 3.5%) compared to placebo combined with an ACE inhibitor. In the Veterans Affairs Nephropathy in Diabetes (VA NEPHRON-D) trial, no additional benefit over monotherapy was seen in patients receiving the combination of losartan and lisinopril compared to monotherapy; however, there was an increased incidence of hyperkalemia and acute renal injury. Patients receiving concomitant therapy with ACE inhibitors and ARBs should be closely monitored for renal dysfunction, hypotension, and hyperkalemia.
Apomorphine: Patients receiving apomorphine may experience orthostatic hypotension, hypotension, and/or syncope. Extreme caution should be exercised if apomorphine is used concurrently with antihypertensive agents, or vasodilators such as nitrates.
Apraclonidine: Alpha blockers as a class may reduce heart rate and blood pressure. While no specific drug interactions have been identified with systemic agents and apraclonidine during clinical trials, it is theoretically possible that additive blood pressure reductions could occur when apraclonidine is combined with the use of antihypertensive agents. Patients using cardiovascular drugs concomitantly with apraclonidine should have their pulse and blood pressure monitored periodically.
Aprepitant, Fosaprepitant: Use caution if valsartan and aprepitant are used concurrently and monitor for a pos |