Spirapril (Renormax) is an ACE inhibitor antihypertensive drug used to treat hypertension. Spiraprilat, the active metabolite of spirapril, competes with angiotensin I for binding at the angiotensin-converting enzyme, blocking the conversion of angiotensin I to angiotensin II. Inhibition of ACE results in decreased plasma angiotensin II. As angiotensin II is a vasoconstrictor and a negative-feedback mediator for renin activity, lower concentrations result in a decrease in blood pressure and stimulation of baroreceptor reflex mechanisms, which leads to decreased vasopressor activity and to decreased aldosterone secretion. Spiraprilat may also act on kininase II, an enzyme identical to ACE that degrades the vasodilator bradykinin.

Spirapril (Renormax) is an ACE inhibitor antihypertensive drug used to treat hypertension. Spiraprilat, the active metabolite of spirapril, competes with angiotensin I for binding at the angiotensin-converting enzyme, blocking the conversion of angiotensin I to angiotensin II. Inhibition of ACE results in decreased plasma angiotensin II. As angiotensin II is a vasoconstrictor and a negative-feedback mediator for renin activity, lower concentrations result in a decrease in blood pressure and stimulation of baroreceptor reflex mechanisms, which leads to decreased vasopressor activity and to decreased aldosterone secretion. Spiraprilat may also act on kininase II, an enzyme identical to ACE that degrades the vasodilator bradykinin.

Bepridil is a calcium channel blocker that has well characterized anti-anginal properties and known but poorly characterized type 1 anti-arrhythmic and anti-hypertensive properties. It has inhibitory effects on both the slow calcium and fast sodium inward currents in myocardial and vascular smooth muscle, interferes with calcium binding to calmodulin, and blocks both voltage and receptor operated calcium channels. It is used to treat hypertension (high blood pressure), angina (chest pain), sustained atrial fibrillation and tachyarrhythmia. The most common side effects were upper gastrointestinal complaints (nausea, dyspepsia or GI distress), diarrhea, dizziness, asthenia and nervousness. Certain drugs could increase the likelihood of potentially serious adverse effects with bepridil hydrochloride. In general, these are drugs that have one or more pharmacologic activities similar to bepridil hydrochloride, including anti-arrhythmic agents such as quinidine and procainamide, cardiac glycosides and tricyclic anti-depressants. Anti-arrhythmics and tricyclic anti-depressants could exaggerate the prolongation of the QT interval observed with bepridil hydrochloride. Cardiac glycosides could exaggerate the depression of AV nodal conduction observed with bepridil hydrochloride.

Bepridil is a calcium channel blocker that has well characterized anti-anginal properties and known but poorly characterized type 1 anti-arrhythmic and anti-hypertensive properties. It has inhibitory effects on both the slow calcium and fast sodium inward currents in myocardial and vascular smooth muscle, interferes with calcium binding to calmodulin, and blocks both voltage and receptor operated calcium channels. It is used to treat hypertension (high blood pressure), angina (chest pain), sustained atrial fibrillation and tachyarrhythmia. The most common side effects were upper gastrointestinal complaints (nausea, dyspepsia or GI distress), diarrhea, dizziness, asthenia and nervousness. Certain drugs could increase the likelihood of potentially serious adverse effects with bepridil hydrochloride. In general, these are drugs that have one or more pharmacologic activities similar to bepridil hydrochloride, including anti-arrhythmic agents such as quinidine and procainamide, cardiac glycosides and tricyclic anti-depressants. Anti-arrhythmics and tricyclic anti-depressants could exaggerate the prolongation of the QT interval observed with bepridil hydrochloride. Cardiac glycosides could exaggerate the depression of AV nodal conduction observed with bepridil hydrochloride.

Pinacidil is a clinically effective vasodilator used for the treatment of hypertension.

Penbutolol is a new beta-adrenergic blocking drug approved for the treatment of hypertension. It is a noncardioselective beta-blocker and has intrinsic sympathomimetic activity. Penbutolol is marketed under the trade names Levatol, Levatolol, Lobeta, Paginol, Hostabloc, Betapressin. Penbutolol acts on the β1 adrenergic receptors in both the heart and the kidney. When β1 receptors are activated by catecholamines, they stimulate a coupled G protein that leads to the conversion of adenosine triphosphate (ATP) to cyclic adenosine monophosphate (cAMP). The increase in cAMP leads to activation of protein kinase A (PKA), which alters the movement of calcium ions in heart muscle and increases the heart rate. Penbutolol blocks the catecholamine activation of β1 adrenergic receptors and decreases heart rate, which lowers blood pressure. Levatol (Penbutolol) is indicated in the treatment of mild to moderate arterial hypertension. It may be used alone or in combination with other antihypertensive agents, especially thiazide-type diuretics.

Penbutolol is a new beta-adrenergic blocking drug approved for the treatment of hypertension. It is a noncardioselective beta-blocker and has intrinsic sympathomimetic activity. Penbutolol is marketed under the trade names Levatol, Levatolol, Lobeta, Paginol, Hostabloc, Betapressin. Penbutolol acts on the β1 adrenergic receptors in both the heart and the kidney. When β1 receptors are activated by catecholamines, they stimulate a coupled G protein that leads to the conversion of adenosine triphosphate (ATP) to cyclic adenosine monophosphate (cAMP). The increase in cAMP leads to activation of protein kinase A (PKA), which alters the movement of calcium ions in heart muscle and increases the heart rate. Penbutolol blocks the catecholamine activation of β1 adrenergic receptors and decreases heart rate, which lowers blood pressure. Levatol (Penbutolol) is indicated in the treatment of mild to moderate arterial hypertension. It may be used alone or in combination with other antihypertensive agents, especially thiazide-type diuretics.

Oxprenolol is clinically a well-established beta blocker that shares with other members of this group the ability to control a variety of disorders, in particular, hypertension and angina. Pharmacologically it is a nonselective beta blocker that possesses partial agonist activity (intrinsic sympathomimetic activity). Pharmacokinetically, oxprenolol behaves as a moderately lipophilic agent. Oxprenolol undergoes first pass metabolism with only 30% of an oral dose reaching the systemic circulation. The drug is approximately 80% protein bound and is eliminated primarily by glucuronidation in the liver. Less than 4% of oxprenolol is excreted unchanged in the urine. Oxprenolol may reduce the heart rate and prolong the effective and functional atrioventricular nodal refractory period. Oxprenolol has less negative inotropic and chronotropic effects than propranolol. Plasma renin activity is reduced; however, changes in plasma aldosterone level are not significant. Long term metabolic effects require further study. Chest pain (angina), high blood pressure (hypertension), irregular heart beats and anxiety are indications for Oxprenolol usage. To date Oxprenolol is discontinued by FDA.

Oxprenolol is clinically a well-established beta blocker that shares with other members of this group the ability to control a variety of disorders, in particular, hypertension and angina. Pharmacologically it is a nonselective beta blocker that possesses partial agonist activity (intrinsic sympathomimetic activity). Pharmacokinetically, oxprenolol behaves as a moderately lipophilic agent. Oxprenolol undergoes first pass metabolism with only 30% of an oral dose reaching the systemic circulation. The drug is approximately 80% protein bound and is eliminated primarily by glucuronidation in the liver. Less than 4% of oxprenolol is excreted unchanged in the urine. Oxprenolol may reduce the heart rate and prolong the effective and functional atrioventricular nodal refractory period. Oxprenolol has less negative inotropic and chronotropic effects than propranolol. Plasma renin activity is reduced; however, changes in plasma aldosterone level are not significant. Long term metabolic effects require further study. Chest pain (angina), high blood pressure (hypertension), irregular heart beats and anxiety are indications for Oxprenolol usage. To date Oxprenolol is discontinued by FDA.

Guanabenz, an antihypertensive agent for oral administration-, is an aminoguanidine derivative, 2,'6-dichlorobenzylideneamina-guanidine acetate. It is white to an almost white powder having not more than a slight odor. Sparingly soluble in water and in 0.1 N hydrochloric acid; soluble in alcohol and in propylene glycol. Guanabenz is an orally active central alpha-2 adrenergic agonist. Its antihypertensive action appears to be mediated via stimulation of central alpha-adrenergic receptors, resulting in a decrease of sympathetic outflow from the brain at the bulbar level to the peripheral circulatory system. In clinical trials, guanabenz acetate, given orally to hypertensive patients, effectively controlled blood pressure without any significant effect on glomerular filtration rate, renal blood flow, body fluid volume or body weight. The Myelin Repair Foundation and the National Institutes of Health (National Institute of Neurological Disorders and Stroke) are developing guanabenz for the treatment of multiple sclerosis. Unlike the currently available treatment for multiple sclerosis that suppresses the immune system, guanabenz, an FDA approved the drug for the treatment of high blood pressure, has a potential to reduce the loss of myelin by protecting and repairing myelin-producing cells in the brain from damage. Phase I development is underway in the US.