Beta-adrenergic receptor blockers (beta-blockers) are effective and safe antihypertensive drugs, and have been recommended as first-line therapy for hypertension by all Joint National Committees (JNCs) for the prevention, detection, evaluation, and treatment of high blood pressure (BP) from the first to the last (JNC-7) in 2003. However, recently questions have been raised by several investigators regarding the antihypertensive effectiveness and safety of these drugs. The Medline literature on this subject was searched and pertinent studies were retrieved. Other pertinent references from existing publications were retrieved and analyzed up to 2007. Additionally, a historical perspective on the discovery of beta-blockers and their mechanism of action is given. Most of the reviewed short-term and long-term clinical trials demonstrate an effective and safe antihypertensive pattern for the beta-blockers. The weaknesses identified include the adverse effect of older beta-blockers on glucose control and stroke protection, especially in older persons. These adverse effects are attributed to their mechanism of action and BP effectiveness. On the basis of the evidence presented, beta-blockers are effective and safe antihypertensive drugs and should still be recommended as first-line therapy in most uncomplicated hypertensive patients, either alone or in combination with other drugs. There are reservations regarding their administration to diabetic and older hypertensive patients. However, when compelling indications for their use exist, they should not be withheld.

No abstract

Olmesartan medoxomil is an angiotensin II (Ang II) receptor blocker (ARB) that has been approved by the US Food and Drug Administration (FDA) for the treatment of hypertension. It is a prodrug that is hydrolysed in the gut into its active metabolite, olmesartan (RNH-6270). Olmesartan is highly selective for the Ang II type 1 receptor (AT1) to which it binds completely and insurmountably and has very little affinity for the other receptor subtypes AT2 and AT4. After oral administration, in animals and humans, it achieves a maximal blood drug concentration within a maximal time of approximately 2 h. It is then slowly eliminated in the urine and faeces. His half-life is approximately 13 h, which makes it suitable for once-daily administration. Olmesartan medoxomil given orally in single daily doses of 20-40 mg has demonstrated significant blood pressure (BP) lowering effects in hypertensive patients. A medline search for the preparation of this manuscript was conducted and revealed 128 references, from 2000 to 2007. Of these, only 16 well-designed prospective clinical trials were selected. The remaining were either animal studies, reviews or studies in progress. In well-designed clinical trials, olmesartan medoxomil has demonstrated similar antihypertensive actions to the other antihypertensive drugs, as well as other members of its class given the highest recommended doses. In addition, the BP lowering effect of olmesartan, like the other members of its class, is greatly enhanced in combination with a diuretic. Its safety profile is similar to the other ARBs and no different than placebo.