What is the effect of taking losartan (Angiotensin II Receptor Antagonist) 50 milligrams orally (PO) daily and amlodipine (Calcium Channel Blocker) 5 milligrams orally (PO) daily?

From the Guidelines

Losartan 50 mg and amlodipine 5 mg taken orally once daily is a suitable combination for hypertension management, but the dose of losartan may need to be increased to 150 mg daily for optimal benefit, as shown in the HEAAL study 1. This combination works through complementary mechanisms: losartan blocks angiotensin II receptors, relaxing blood vessels and reducing fluid retention, while amlodipine is a calcium channel blocker that relaxes and widens blood vessels. The key evidence from the CHARM-Added trial and Val-HeFT study indicates that ARBs, such as losartan, reduce the risk of HF hospitalization and improve symptoms and quality of life when added to conventional treatment, including ACE inhibitors and beta-blockers 1. Additionally, the 2007 guidelines for the management of arterial hypertension suggest that antihypertensive treatment, including calcium antagonists like amlodipine, is beneficial in patients with coronary heart disease and heart failure, and that the benefit is related to the degree of blood pressure reduction 1. It is essential to monitor blood pressure and adjust the treatment as needed to achieve optimal blood pressure control. Common side effects of losartan include dizziness and occasional cough, while amlodipine may cause mild ankle swelling. Blood pressure monitoring is recommended, especially when starting this combination, and periodic laboratory tests to check kidney function and electrolytes are important. If experiencing severe dizziness, significant swelling, or difficulty breathing, contact your healthcare provider immediately. This combination provides more comprehensive blood pressure control than either medication alone by targeting different physiological pathways involved in blood pressure regulation. Some key points to consider when using this combination include:

• Monitoring blood pressure regularly to adjust the treatment as needed
• Checking kidney function and electrolytes periodically
• Being aware of potential side effects, such as dizziness and ankle swelling
• Considering an increase in the dose of losartan to 150 mg daily for optimal benefit, as supported by the HEAAL study 1.

From the FDA Drug Label

After one month, investigators were instructed to titrate study drug to 100 mg once daily if the trough blood pressure goal (140/90 mmHg) was not achieved. Because the study was designed to achieve equal blood pressure control in both groups, other antihypertensive agents (diuretics, calcium-channel blockers, alpha- or beta-blockers, and centrally acting agents) could be added as needed in both groups.

The patient is taking losartan 50 mg PO DAILY and amlodipine 5 mg PO DAILY.

• Losartan is an angiotensin II receptor antagonist, and the study shows that it can be used with other antihypertensive agents, including calcium-channel blockers like amlodipine.
• The study does not provide information on the specific dosage of losartan and amlodipine that should be used together, but it does show that losartan can be titrated to 100 mg once daily if the trough blood pressure goal is not achieved.
• The use of losartan with amlodipine is not contraindicated, and the study suggests that losartan can be effective in reducing blood pressure and slowing the progression of renal disease when used with other antihypertensive agents 2.

From the Research

Medication Comparison

• Losartan 50 mg PO daily and amlodipine 5 mg PO daily are being compared for their effects on blood pressure and renal function.
• Studies have shown that losartan has a renoprotective effect, reducing proteinuria in patients with chronic kidney disease and hypertension 3, 4.
• Amlodipine, on the other hand, has been shown to have a lesser effect on proteinuria, with some studies indicating no significant reduction in urinary albumin excretion 4, 5.

Blood Pressure Reduction

• Both losartan and amlodipine have been shown to reduce blood pressure in hypertensive patients, with similar efficacy in some studies 6, 7.
• However, one study found that amlodipine had a longer-lasting antihypertensive effect, with a greater trough-to-peak ratio of antihypertensive effect on systolic blood pressure 5.

Combination Therapy

• The combination of losartan and amlodipine has been studied, with one trial finding that the fixed-dose combination of amlodipine 5 mg/losartan 50 mg was not inferior to amlodipine 10 mg monotherapy in reducing diastolic blood pressure 7.
• Another study found that the combination of losartan and hydrochlorothiazide was effective in reducing blood pressure, with a similar efficacy to the combination of candesartan and amlodipine 6.

Renal Effects

• Losartan has been shown to have a renoprotective effect, reducing proteinuria and slowing the progression of chronic kidney disease 3, 4.
• Amlodipine, on the other hand, has been found to have a lesser effect on renal function, with some studies indicating no significant reduction in proteinuria 4, 5.