Sitaxentan (TBC11251, trade name Thelin) is a potent and selective Endothelin A receptor antagonist. Sitaxentan was under development by Encysive Pharmaceuticals (now Pfizer) for use in the treatment of pulmonary hypertension, congestive heart failure and asthma. It was launched in the major markets of the European Union (EU) under name Thelin for the treatment of pulmonary arterial hypertension. In December 2010, Pfizer discontinued clinical trials of sitaxentan worldwide and initiated voluntary product withdrawal from markets where it is approved due to life-threatening idiosyncratic risk of liver injury.

Cadralazine is an antihypertensive of the hydrazinophthalazine chemical class. In hypertensive patients the optimal effect, based on the antihypertensive efficacy to tolerability ratio, is seen after a 15 mg dose when the drug is administered as monotherapy. When administered in combination with other antihypertensive agents, a 10 mg daily dosage seems appropriate. Noncomparative trials have shown that, in patients who had failed to respond adequately to a beta-blocker and/or diuretic, the addition of cadralazine 10 to 30 mg once daily reduced systolic/diastolic blood pressure by 11 to 19%/13 to 22%. This antihypertensive effect becomes evident over a 2- to 6-week period of therapy and persists during longer term administration. Comparative studies have shown that cadralazine is superior to placebo, and has a similar blood pressure lowering effect to hydralazine, dihydralazine and prazosin in patients not controlled by beta-blocker and/or diuretic but who continued to receive these treatments. Similarly, cadralazine and chlorthalidone were equally effective in reducing blood pressure in resting hypertensive patients but cadralazine shows an advantage in reducing the pressor response in exercising patients. Cadralazine is well tolerated when administered with a beta-blocker or diuretic. Most adverse effects become less frequent and severe with continued use, occur more frequently at dosages of 20 mg/day or more, and do not generally require withdrawal of therapy. Manifestations of the drug's vasodilating properties such as headache, asthenia, dizziness, palpitations and flushing are the most commonly reported symptoms during cadralazine monotherapy, but these may be reduced during combination therapy. The drug does not appear to induce a systemic lupus-like erythematosus syndrome, as may occur with hydralazine, but additional clinical experience is required to completely exclude this possibility. The therapeutic potential of cadralazine cannot be clearly established until the present limited clinical base is expanded to include comparisons with other classes of vasodilating drugs (ACE inhibitors and calcium antagonists), and its utility in the management of other indications such as severe hypertension during pregnancy has been adequately explored.

Naftazone is a naphtoquinone derivative which was originally registered in several European countries for treating symptoms of varicose veins and venous insufficiency, based on its venoconstrictive properties. ts venotonic mechanism of action remains unknown, but the drug has anti‐inflammatory effects and inhibits platelet aggregation. Naftazone is shown to accelerate human saphenous vein endothelial cell proliferation in vitro at concentrations which did not alter the hemostatic balance. Naftazone, which exhibits glutamate release inhibition properties, has shown antiparkinsonian and antidyskinetic activity in preclinical models of Parkinson's disease and in a clinical proof of concept study. Naftazone is currently marketed in several countries.

Ibopamine is the prodrug of epinine or N-methyl dopamine. Ibopamine stimulates the DA1 and DA2 dopaminergic receptors, the beta 1 and beta 2 adrenoceptors, and the alpha 1 and alpha 2 adrenoceptors. Ibopamine has varying degrees of affinity for these various families, being the highest for the dopamine receptors and the lowest for the alpha adrenergic receptors. Ibopamine reduces systemic vascular resistance, increases cardiac output, and increases renal flow. Ibopamine also modulates the neuroendocrine reflexes in heart failure; plasma renin activity and norepinephrine and aldosterone plasma concentrations are reduced, both immediately and during sustained administration. In patients with heart failure (HF), low doses appear to exert beneficial neurohormonal, hemodynamic, and renal effects, without increased inotropic effects. However, at higher doses (> 200 mg) ibopamine exerts effects that do not appear to be clinically useful in long-term treatment of chronic HF. Several small trials have suggested a benefit of ibopamine on exercise performance in patients with mild to moderate HF. On the basis of these studies, ibopamine is now being used in Europe to treat patients with mild to moderate congestive heart failure (CHF). At doses of 100 or 200 mg/t.i.d., there has been no evidence of significant safety problems. Ibopamine was used in Europe to treat heart failure. In 1995, a study showed that ibopamine increased death rates in patients who had moderate to severe heart failure. In September 1995, doctors and pharmacists in the Netherlands were officially notified that ibopamine should be used only in patients with mild heart failure. Moreover, the official recommendations for when to use ibopamine were changed according to whether patients had mild or severe heart failure. Ibopamine, a sympathomimetic drug, is used in ophthalmology. t has a not-cycloplegic mydriatic activity. Its peak of action is at 45 minutes after instillation in the conjunctival sac. Its action lasts after about 360 minutes. Its D1-dopaminergic stimulation increases the aqueous humor production and it is a provocative test for evaluating the function of aqueous humor outflow structures also in relatives of glaucomatous patients. It is also useful to treat ocular hypotension. Its main use is in every ophthalmological assessment, either diagnostic or preoperative, where the cycloplegia is not adviced. It is useful for the safe mydriasis of patients treated with α-1 adrenergic receptor antagonists.

Piretanide (INN, trade names Arelix, Eurelix, Tauliz) has been synthesized in 1973 at Hoechst AG (Germany) as a loop diuretic[2] compound by using a then-new method for introducing cyclic amine residues in an aromatic nucleus in the presence of other aromatically bonded functional groups. Studies of piretanide in rats and dogs in comparison with other high-ceiling diuretics such as furosemide and bumetanide found a more suitable dose/response rate (regression line) and a more favourable sodium/potassium excretion ratio. These findings led eventually to clinical studies in man and finally to the introduction as a saluretic and antihypertensive medication in Germany, France, Italy and other countries.

Trimetazidine is a medicine, which is used for the treatment of angina pectoris. The drug mechanism of action is explained by its ability to selectively inhibit long-chain 3-ketoacyl coenzyme A thiolase, an enzyme responsible for mitochondrial beta-oxidation of long chain fatty acids. Trimetazidine also increases pyruvate dehydrogenase activity, binds to the mitochondrial membrane, directly inhibits cardiac fibrosis and improves mechanical resistance of the sarcolemma.

Imolamine is a coronary vasodilator, which is used in the treatment of angina pectoris and as a local anesthetic. Imolamine has been shown to produce in animals coronary vasodilation, local anaesthesia, analgesia and a papaverine like action in duodenal preparations. Imolamine increased the tone of uterus and ileum and this was accompanied by a reduction in amplitude of contraction. The response of the stomach tissue to imolamine was similar to that of butalamine and aminophylline, i.e. a relaxant action on smooth muscle. Imolamine has a variable action on tone, producing an increase in ileum and uterus and a decrease in stomach. Imolamine is able to cause severe cytolytic hepatitis.

Fenquizone is the diuretic drug. The distribution of fenquizone labelled with 14C in mice was studied by means of an autoradiographic technique. High concentration of radioactivity was found in the intestine, liver, kidney, blood, myocardium and skeletal muscles in decreasing order at various times after oral administration. The labelled compound did not cross the blood-brain barrier. Fenquizone is a saluretic with a quinazolone structure which acts by blocking reabsorption of sodium in the proximal tubule and the ascending branch of the loop of Henle, as well as in the proximal section of the convoluted distal tubule. At low doses fenquizone has an hypotensive action without showing the characteristics secondary effects of diuretics so that it can be employed for long-term treatments without any risk. Fenquizone showed also a significant decrease of symptoms (headache, dizziness) due to hypertension. No undesirable side effects were observed.

Methoserpidine is a synthetic isomer of reserpine, used in the 1960s as an antihypertensive drug. Initially, it was reported to be free from CNS side effects of reserpine (mild suppression of alertness, and mental depression). However, later clinical experience has shown that in a significant proportion of patients administration of the drug lead to episodes of depression.

Ciprofibrate is an orally active phenoxyisobutyrate hypolipidemic compound. It acts by activating peroxisome proliferator activated receptor alpha. Ciprofibrate is efficacious for the correction of hyperlipidaemias.