Benicar Review Article
Benicar (Generic Name: Olmesartan Medoxomi) is an antagonist of Angiotensin II receptor and is prescribed for people suffering from hypertension. It may be used as a first-line medication and may be utilized by itself or with other anti-hypertensive agents. On the other hand, Benicar HCT merges hydrochlorothiazide or HCTZ with Benicar. HCTZ is a thiazide diuretic. The combination in Benicar HCT provides much greater reduction in blood pressure. The combination of the two drugs is shown to have a complementary effect in decreasing the blood pressure. Side effects of Benicar may include dizziness while contraindications include pregnancy and Biliary obstruction. BENICAR AND BENICAR HCT MUST NOT BE USED DURING PREGNANCY. IT CAN CAUSE INJURY AND DEATH TO THE GROWING FETUS.
Blood pressure is defined as the force exerted by the blood against artery walls as it is being pumped by the heart (National Institute of Health). It is measured through two values – the systolic blood pressure and the diastolic blood pressure, which represents the force on the arteries as the heart contracts and relaxes to pump out blood. Continue reading...
Benicar generic (generic - what is it?)
||Add to basket
Hypertension, or high blood pressure, is a condition wherein there is elevated systolic, diastolic, or both systolic and diastolic blood pressure (National Institute of Health). This increase in pressure may be temporary or chronic, and is classified into stages according to the degree of elevation. The latest report from the Joint National Committee on the Prevention, Detection Evaluation and Treatment of High Blood Pressure (JNC 7) has released an official classification system for blood pressure measurements, which is based on the average of two or more properly measured, seated blood pressure readings on two or more office visits.
Reference: The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure
The prehypertension category was included to identify persons at risk for developing hypertension, in order for patients and clinicians to be alerted and encouraged to employ appropriate preventive measures. Unlike the stage 1 and stage 2 hypertension categories, though, this category does not necessitate drug therapy.
Several factors have been identified to play a role in blood pressure elevation. Because of this, two forms of hypertension are recognized: primary (or essential hypertension), and secondary hypertension. Of the two, essential hypertension is the more common, accounting for up to 95% of all cases (Medicine Net). Essential hypertension has a multi-factorial etiology, which may include high salt intake, increasing age, African-American descent, obesity, family history, smoking, alcohol consumption, and stressful lifestyle. Secondary hypertension, on the other hand, is associated with a specific disorder in one or more organ systems. Diabetes, chronic kidney disease, adrenal gland disorders, pregnancy, coarctation of the aorta, and hyperparathyroidism have all been pointed out as common causes of blood pressure elevation (National Institute of Health).
An estimated 50 million people in the United States are living with hypertension. Worldwide, it is said to affect 20% of the adult population, and 50% of all adults aged 60 years and above. Also, despite substantial improvements in raising awareness regarding the disease, up to 67% of all hypertensive cases are still uncontrolled (JNC 7).
Dubbed as “the silent killer”, hypertension often does not present with symptoms, although more severe cases may experience headache, nausea, blurry vision, and dizziness. Despite this, it is a very common risk factor to many diseases such as heart attack, heart failure, kidney disease, and stroke (National Institute of Health). This is because it causes added stress to the heart and to the lining of the blood vessels, leading to damage. However, as it is a common condition, many treatments have been made available to help lower blood pressure and help it retain it within normal levels.
Hypertension, in most cases, is a lifetime condition which requires long-term treatment. According to the JNC 7, the ultimate goal of antihypertensive therapy is to reduce the person’s risk for cardiovascular and renal complications by normalizing the blood pressure to acceptable levels. Blood pressure control has been associated with significant risk reductions for many complications, decreasing stroke risk by up to 40%, myocardial infarction by up to 25%, and heart failure by more than 50%. The blood pressure goal depends on the stage of the disease as well as the presence of co-morbid conditions such as diabetes or renal disease.
Lifestyle modifications are recognized as an indispensable feature of antihypertensive therapy (JNC 7). These include weight reduction, adoption of the DASH (Dietary Approaches to Stop Hypertension) eating plan which involves increased consumption of fruits, vegetables, and non-fat dairy as well as reduced consumption of fat and salt, increased physical activity, smoking cessation, and alcohol intake reduction.
Pharmacologic treatment using antihypertensive drugs is also recommended to achieve significant blood pressure reduction in patients with stage 1 and stage 2 hypertension. For most patients, only one antihypertensive drug is recommended as part of the treatment plan. However, in patients with substantially higher blood pressures or with co-morbid conditions, a combination of two or three drugs is usually required.
A wide variety of oral antihypertensive drugs have been developed through the years. Such classes of drugs include: diuretics, beta-blockers, ACE inhibitors, Angiotensin II receptor blockers, calcium channel blockers, centrally-acting drugs, and direct vasodilators. Each drug class lowers blood pressure by a different mechanism.
Drugs such as ACE inhibitors and Angiotensin II receptor blockers (ARBs) work by influencing the renin-angiotensin-aldosterone system (RAAS). In this system, a substance called renin is released by the kidneys, which acts upon the substrate angiotensinogen to form a chemical called angiotensin I. The pulmonary endothelium then releases an enzyme called angiotensin converting enzyme (ACE), which causes angiotensin I to become angiotensin II. Angiotensin II is a potent chemical substance which causes blood vessels to contract and stimulates the release of aldosterone, resulting in elevation of blood pressure.
ARBs exert their action by binding to the receptors of angiotensin II in the blood vessels, thus blocking the action of the substance and preventing vasoconstriction. As a result, the blood vessels dilate and blood pressure is lowered. In the clinical setting, though both ARB and ACE inhibitors act on the RAAS and have the same efficacy, ARBs are preferred over ACE inhibitors because of the better side effect profile of ARBs. Many ARBs have been discovered and approved throughout the years, the most recent of which is olmesartan medoxomil, commercially marketed by Sankyo Pharma as Benicar®.
Benicar is a selective AT1 subtype antihypertensive agent belonging to the drug class of angiotensin II receptor blockers (ARBs). It is a prodrug which is hydrolyzed to olmesartan in the gastrointestinal tract. Its molecular formula is C29H30N6O6, with the structural formula:
Benicar was approved by the U.S. Food and Drug Administration in April of 2002 for treatment of hypertension, alone or with other antihypertensive agents.
Efficacy of Benicar
Benicar, just like other ARBs exerts its antihypertensive activity by causing selective blockade of the angiotensin II receptors in the vascular muscles. This causes lowering of the blood pressure by promoting vasodilation and reducing salt and water retention.
The efficacy of Benicar has been assessed in several comparison studies. One such study is by Puchler et al. (1999), wherein randomized patients were assigned to different doses of Benicar ranging from 2.5 mg/d to 80 mg/d. After 12 weeks, a significant blood pressure reduction was observed in treatment groups receiving doses of 10 mg/d and above. In a meta-analysis conducted by Neutel (2001), he integrated data from 7 parallel randomized clinical trials in which monotherapy using Benicar was instituted. A dose-dependent reduction in both systolic and diastolic blood pressure was observed within one week of treatment, with the maximal response being achieved within 2 weeks. Benicar was also observed to have a peak effect 24 hours after administration, making it suitable for once-daily dosing.
Benicar vs. other ARBs
Although similar to other ARBs in terms of structure and pharmacological effects, Benicar has been found to be superior to other ARBs in terms of affinity to the angiotensin (AT) receptor, leading to better binding and stronger potency.
Benicar has been found to have a 12,500-fold better binding affinity to the AT1 receptor subtype, which is responsible for the majority of vascular responses. In separate studies by Herbert et al. (1994), de Gasparo et al. (1995), and Edwards et al. (1992), Benicar was shown to possess the second strongest AT1 receptor affinity among all ARBs, next to valsartan.
In another study by Ball in 2001, he compared Benicar to Losartan. After two, four, eight, and twelve weeks, Benicar was associated with a significantly greater systolic and diastolic blood pressure reduction than losartan. At 16, 20, and 24 weeks however, no significant difference was found between the two drugs.
Aside from losartan, Benicar was also compared to other ARBs such as valsartan and irbesartan. A double-blind, parallel study conducted by Oparil, et al. (2001) showed that after eight weeks of treatment, there was a significantly higher reduction in diastolic blood pressure in patients receiving Benicar than in patients receiving the other ARBs.
Benicar vs. other antihypertensives
Benicar has also been found to be comparable to other antihypertensive drugs. In a 2001 study by Van Mieghem, Benicar was shown to be at least as effective as atenolol in reducing diastolic blood pressure after four weeks of treatment, and a significantly higher reduction in systolic blood pressure.
Williams (2001) compared the effect of Benicar to the ACE inhibitor captopril in 291 patients with mild to moderate hypertension. After 12 weeks, Benicar has been shown to be superior to captopril in both systolic and diastolic blood pressure reduction.
In a 2003 study by Chrysant et al., 440 patients with mild to moderate hypertension were treated with Benicar, amlodipine, or placebo for eight weeks. After the treatment period, it was found that patients receiving Benicar and amlodipine achieved similar reductions in blood pressure, although more patients in the Benicar treatment group achieved blood pressure control than the amlodipine group.
Dosage of Benicar
According to a report by von Bergmann et al. (2001), the recommended initial dose of Benicar is 20 mg/day, taken once daily. If no significant reduction is observed after two weeks, the dose can be doubled to 40 mg/day. In elderly patients, as well as in those with renal or hepatic impairment, a maximum dose 20 mg/day is recommended.
A.D.A.M. Inc. 2011. Hypertension. Retrieved from: http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0001502/
BALL, K.J. et al. 2001. Relative efficacy of an angiotensin II antagonist compared with other antihypertensive agents: olmesartan medoxomil versus antihypertensives. Retrieved from: http://www.ncbi.nlm.nih.gov/pubmed/11451215
CHRYSANT, S.G. 2003. The antihypertensive efficacy and safety of olmesartan medoxomil compared with amlodipine for mild-to-moderate hypertension. Retrieved from: http://www.nature.com/jhh/journal/v17/n6/full/1001577a.html
CUNHA, J.P. High blood pressure (hypertension). Retrieved from: http://www.medicinenet.com/high_blood_pressure/article.htm#toc1bp
DE GASPARO, M., WHITEBREAD, S. 1995. Binding of valsartan to mammalian angiotensin AT1 receptors. Retrieved from: http://www.ncbi.nlm.nih.gov/pubmed/8577935
EDWARDS, R.M. et al. 1992. Pharmacological characterization of the nonpeptide angiotensin II receptor antagonist, SK&F 108566. Retrieved from: http://www.ncbi.nlm.nih.gov/pubmed/1309870
HERBER, J.M. et al. 1994, Effect of SR 47436, a novel angiotensin II AT1 receptor antagonist, on human vascular smooth muscle cells in vitro. Retrieved from: http://www.ncbi.nlm.nih.gov/pubmed/8149971
KAMRAN, R. 2011. Hypertension. Retrieved from: http://emedicine.medscape.com/article/241381-overview#a0101
NATIONAL HEART, LUNG AND BLOOD INSTITUTE. 2004. The seventh report of the Joint National Committee on prevention, detection, evaluation and treatment of high blood pressure. Retrieved from
NEUTEL, J.M. 2001. Clinical studies of CS-866, the newest angiotensin II receptor antagonist. Retrieved from: http://www.ncbi.nlm.nih.gov/pubmed/11334767
OMUDHOME, O. Angiotensin II receptor blockers (ARBs). Retrieved from: http://www.medicinenet.com/angiotensin_ii_receptor_blockers/article.htm
OPARIL, S. et al. 2001. Comparative efficacy of olmesartan, losartan, valsartan, and irbesartan in the control of essential hypertension. Retrieved from: http://onlinelibrary.wiley.com/doi/10.1111/j.1524-6175.2001.01136.x/abstract
PUCHLER, K. et al. 1999. Safety, tolerability and efficacy of the new angiotensin II (AT1)-receptor antagonist CS-866 in patients with mild to moderate hypertension. Journal of Human Hypertension. Vol 13, issue 4.
RXLIST, INC. 2011. Benicar. Retrieved from: http://www.rxlist.com/benicar-drug.htm
VAN MIEGHEM, W. 2001. A multicentre, double-blind, efficacy, tolerability, and safety study of the oral angiotensin II antagonist olmesartan medoxomil versus atenolol in patients with mild to moderate essential hypertension. Journal of Hypertension, vol. 19, p. 152.
VON BERGMANN, K. et al. 2001. Olmesartan medoxomil: influence of age, renal and hepatic function on the pharmacokinetics of olmesartan medoxomil. Retrieved from: http://www.ncbi.nlm.nih.gov/pubmed/11451213
WILLIAMS, P.A. A multi-centre, double-blind, efficacy, tolerability and safety study of the oral angiotensin II antagonist olmesartan medoxomil versus captopril in patients with mild to moderate essential hypertension. Journal of Hypertension, vol. 19, p. 300.
Benicar Review Article