Ramipril (sold under the brand name Altace ) is a prodrug belonging to the angiotensin-converting enzyme (ACE) inhibitors. It is metabolized to ramiprilat in the liver and, to a lesser extent, kidneys. Ramiprilat is a potent, competitive inhibitor of ACE, the enzyme responsible for the conversion of angiotensin I (ATI) to angiotensin II (ATII). ATII regulates blood pressure and is a key component of the renin-angiotensin-aldosterone system (RAAS). Ramipril is indicated for the treatment of hypertension, to lower blood pressure; also used to reduce the risk of myocardial infarction, stroke, or death from cardiovascular causes; in addition, this drug is used to reduce the rate of death, myocardial infarction and stroke in individuals at high risk of cardiovascular events.

Benazepril is a prodrug which is metabolized by the liver into its active form benazeprilat via cleavage of the drug's ester group. Benazepril and Benazeprilat inhibit angiotensin-converting enzyme (ACE) in human subjects and animals. Benazeprilat has much greater ACE inhibitory activity than does Benazepril. It is indicated for the treatment of hypertension. It may be used alone or in combination with thiazide diuretics. Adverse reactions reported in controlled clinical trials and rarer events seen in post-marketing experience, include the following: Stevens-Johnson syndrome, pemphigus, apparent hypersensitivity reactions (manifested by dermatitis, pruritus, or rash), photosensitivity, and flushing, nausea, pancreatitis, constipation, gastritis, vomiting, and melena, thrombocytopenia and hemolytic anemia, anxiety, decreased libido, hypertonia, insomnia, nervousness, and paresthesia. Patients on diuretics, especially those in whom diuretic therapy was recently instituted, may occasionally experience an excessive reduction of blood pressure after initiation of therapy with Benazepril. Increased serum lithium levels and symptoms of lithium toxicity have been reported in patients receiving ACE inhibitors (including benazepril) during therapy with lithium.

Quinapril is the hydrochloride salt of quinapril, the ethyl ester of a non-sulfhydryl, angiotensin-converting enzyme (ACE) inhibitor, quinaprilat. Quinapril hydrochloride is a white to off-white amorphous powder that is freely soluble in aqueous solvents. Quinapril is indicated for the treatment of high blood pressure (hypertension) and as adjunctive therapy in the management of heart failure. It may be used for the treatment of hypertension by itself or in combination with thiazide diuretics, and with diuretics and digoxin for heart failure.

Fosinopril is a phosphinic acid-containing ester prodrug that belongs to the angiotensin-converting enzyme (ACE) inhibitor class of medications. It is rapidly hydrolyzed to fosinoprilat, its principle active metabolite. Fosinoprilat inhibits ACE, the enzyme responsible for the conversion of angiotensin I (ATI) to angiotensin II (ATII). ATII regulates blood pressure and is a key component of the renin-angiotensin-aldosterone system (RAAS). Fosinopril may be used to treat mild to moderate hypertension, as an adjunct in the treatment of congestive heart failure, and to slow the rate of progression of renal disease in hypertensive individuals with diabetes mellitus and microalbuminuria or overt nephropathy.

Felodipine is a long-acting 1,4-dihydropyridine calcium channel blocker (CCB)b. It acts primarily on vascular smooth muscle cells by stabilizing voltage-gated L-type calcium channels in their inactive conformation. By inhibiting the influx of calcium in smooth muscle cells, felodipine prevents calcium-dependent myocyte contraction and vasoconstriction. Felodipine is the most potent CCB in use and is unique in that it exhibits fluorescent activity. In addition to binding to L-type calcium channels, felodipine binds to a number of calcium-binding proteins, exhibits competitive antagonism of the mineralcorticoid receptor, inhibits the activity of calmodulin-dependent cyclic nucleotide phosphodiesterase, and blocks calcium influx through voltage-gated T-type calcium channels. Felodipine is used to treat mild to moderate essential hypertension.

Doxazosin mesylate is a quinazoline compound sold by Pfizer under the brand name CARDURA. CARDURA is indicated for the treatment of both the urinary outflow obstruction and obstructive and irritative symptoms associated with BPH: obstructive symptoms (hesitation, intermittency, dribbling, weak urinary stream, incomplete emptying of the bladder) and irritative symptoms (nocturia, daytime frequency, urgency, burning). CARDURA may be used in all BPH patients whether hypertensive or normotensive. In patients with hypertension and BPH, both conditions were effectively treated with CARDURA monotherapy. CARDURA provides rapid improvement in symptoms and urinary flow rate in 66–71% of patients. CARDURA is also indicated for the treatment of hypertension. CARDURA may be used alone or in combination with diuretics, beta-adrenergic blocking agents, calcium channel blockers, or angiotensin-converting enzyme inhibitors. Doxazosin acts by inhibiting the postsynaptic alpha(1)-adrenoceptors on vascular smooth muscle. This inhibits the vasoconstrictor effect of circulating and locally released catecholamines (epinephrine and norepinephrine), resulting in peripheral vasodilation.

Isradipine (tradenames DynaCirc, Prescal) is a calcium channel blocker of the dihydropyridine class. It is usually prescribed for the treatment of high blood pressure in order to reduce the risk of stroke and heart attack. Except for diuretic activity, the mechanism of which is not clearly understood, the pharmacodynamics effects of isradipine observed in whole animals can also be explained by calcium channel blocking activity, especially dilating effects in arterioles, which reduce systemic resistance and lower blood pressure, with a small increase in resting heart rate. Isradipine binds to calcium channels with high affinity and specificity and inhibits calcium flux into cardiac and arterial smooth muscle cells. It exhibits greater selectivity towards arterial smooth muscle cells owing to alternative splicing of the alpha-1 subunit of the channel and increased prevalence of inactive channels in smooth muscle cells. Although like other dihydropyridine calcium channel blockers, isradipine has negative inotropic effects in vitro; studies conducted in intact anesthetized animals have shown that the vasodilating effect occurs at doses lower than those do which affect contractility. In patients with normal ventricular function, isradipine's afterload reducing properties lead to some increase in cardiac output. Effects in patients with impaired ventricular function have not been fully studied. Most adverse reactions were mild and related to the vasodilatory effects of isradipine (dizziness, edema, palpitations, flushing, tachycardia), and many were transient. About 5% of isradipine patients left studies prematurely because of adverse reactions (vs. 3% of placebo patients and 6% of active control patients), principally due to headache, edema, dizziness, palpitations, and gastrointestinal disturbances.

Nicardipine is a potent calcium channel blockader with marked vasodilator action used to treat high blood pressure and angina. By deforming the channel, inhibiting ion-control gating mechanisms, and/or interfering with the release of calcium from the sarcoplasmic reticulum, nicardipine inhibits the influx of extracellular calcium across the myocardial and vascular smooth muscle cell membranes The decrease in intracellular calcium inhibits the contractile processes of the myocardial smooth muscle cells, causing dilation of the coronary and systemic arteries, increased oxygen delivery to the myocardial tissue, decreased total peripheral resistance, decreased systemic blood pressure, and decreased afterload.

Amlodipine is a dihydropyridine calcium antagonist (calcium ion antagonist or slow-channel blocker) that inhibits the transmembrane influx of calcium ions into vascular smooth muscle and cardiac muscle. Experimental data suggest that amlodipine binds to both dihydropyridine and nondihydropyridine binding sites. The contractile processes of cardiac muscle and vascular smooth muscle are dependent upon the movement of extracellular calcium ions into these cells through specific ion channels. Amlodipine inhibits calcium ion influx across cell membranes selectively, with a greater effect on vascular mooth muscle cells than on cardiac muscle cells. Amlodipine is indicated for the treatment of hypertension and coronary artery disease.

Terazosin (marketed as Hytrin or Zayasel) is a selective alpha1-antagonist used for treatment of symptoms of benign prostatic hyperplasia (BPH). It also acts to lower blood pressure, so it is a drug of choice for men with hypertension and prostate enlargement. All three receptor subtypes appear to be involved in maintaining vascular tone. The α1A-receptor maintains basal vascular tone while the α1B-receptor mediates the vasocontrictory effects of exogenous α1-agonists. Activation of α1-receptors activates Gq-proteins, which results in intracellular stimulation of phospholipases C, A2, and D. This results in mobilization of Ca2+ from intracellular stores, activation of mitogen-activated kinase and PI3 kinase pathways and subsequent vasoconstriction.