Zaleplon is a nonbenzodiazepine hypnotic from the pyrazolopyrimidine class and is indicated for the short-term treatment of insomnia. While Zaleplon is a hypnotic agent with a chemical structure unrelated to benzodiazepines, barbiturates, or other drugs with known hypnotic properties, it interacts with the gamma-aminobutyric acid-benzodiazepine (GABABZ) receptor complex. Subunit modulation of the GABABZ receptor chloride channel macromolecular complex is hypothesized to be responsible for some of the pharmacological properties of benzodiazepines, which include sedative, anxiolytic, muscle relaxant, and anticonvulsive effects in animal models. Zaleplon also binds selectively to the CNS GABAA-receptor chloride ionophore complex at benzodiazepine(BZ) omega-1 (BZ1, ο1) receptors. Zaleplon exerts its action through subunit modulation of the GABABZ receptor chloride channel macromolecular complex. Zaleplon also binds selectively to the brain omega-1 receptor located on the alpha subunit of the GABA-A/chloride ion channel receptor complex and potentiates t-butyl-bicyclophosphorothionate (TBPS) binding. Zaleplon is marketed under the brand names Sonata, Starnoc, and Andante.

Cilostazol is a PDE3 inhibitor which is used for the treatment of intermittent claudication. The drug positively affects the platelet aggregation and may be used off-label as a measure to prevent coronary thrombosis/restenosis and stroke recurrence.

Paricalcitol (Zemplar) is a synthetic vitamin D(2) analogue that inhibits the secretion of parathyroid hormone (PTH) through binding to the vitamin D receptor. It is approved in the US and in most European nations for intravenous use in the prevention and treatment of secondary hyperparathyroidism associated with chronic renal failure in adult, and in the US paediatric, patients. Paricalcitol effectively reduced elevated serum PTH levels and was generally well tolerated in children and adults with secondary hyperparathyroidism associated with chronic renal failure. In well designed clinical trials, paricalcitol was as effective as calcitriol and as well tolerated in terms of the incidence of prolonged hypercalcaemia and/or elevated calcium-phosphorus product (Ca x P). Preclinical and in vitro studies have demonstrated that paricalcitol's biological actions are mediated through binding of the vitamin D receptor, which results in the selective activation of vitamin D responsive pathways. Vitamin D and paricalcitol have been shown to reduce parathyroid hormone levels by inhibiting PTH synthesis and secretion.

Anagrelide is an orally active quinazinolone derivative that was originally developed as an antiplatelet drug. The drug inhibits cyclic nucleotide phosphodiesterase III (PDEIII) and phopholipase A2, which is thought to cause the side effects of vasodilation, positive inotropism, reduced platelet aggregation. However, significant inhibition of platelet aggregation is observed only at doses of anagrelide higher than those required to reduce platelet count. It is indicated for the treatment of patients with thrombocythemia, secondary to myeloproliferative disorders. Commonly reported side effects of anagrelide include: abdominal pain, dizziness, headache, nausea, and palpitations. Other side effects include: back pain, fever, tachycardia, vomiting, and anorexia. There is a single case report, which suggests that sucralfate may interfere with anagrelide absorption. Anagrelide is an inhibitor of cyclic AMP PDE III. The effects of medicinal products with similar properties such as inotropes milrinone, enoximone, amrinone, olprinone and cilostazol may be exacerbated by anagrelide.

Atorvastatin calcium (LIPITOR®) is a pyrrole and heptanoic acid derivative, a synthetic lipid-lowering agent. Atorvastatin is a selective, competitive inhibitor of 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase. This enzyme catalyzes the conversion of HMG-CoA to mevalonate, an early and rate-limiting step in cholesterol biosynthesis. Atorvastatin is used to reduce serum levels of LDL(low-density lipoprotein)-cholesterol; apolipoprotein B; and triglycerides and to increase serum levels of HDL(high-density lipoprotein)-cholesterol in the treatment of hyperlipidemias and prevention of cardiovascular disease in patients with multiple risk factors.

Ritonavir is a protease inhibitor with activity against Human Immunodeficiency Virus Type 1 (HIV-1). Ritonavir binds to the protease active site and inhibits the activity of the enzyme. It is FDA approved for the treatment of HIV-1 infection. In patients receiving medications metabolized by CYP3A or initiation of medications metabolized by CYP3A in patients already receiving Ritonavir, may increase plasma concentrations of medications metabolized by CYP3A. The most frequently reported adverse drug reactions among patients receiving Ritonavir alone or in combination with other antiretroviral drugs were gastrointestinal (including diarrhea, nausea, vomiting, abdominal pain (upper and lower)), neurological disturbances (including paresthesia and oral paresthesia), rash, and fatigue/asthenia.

Iodixanol (brand name VISIPAQUE) is an iodine-containing nonionic dimeric hydrophilic contrast agent for intravascular (intravenous and intra-arterial) use during coronary angiography. Pharmacodynamics studies indicated that iodixanol had fewer cardiovascular effects, caused less renal damage and were associated with similar or smaller changes to the blood-brain barrier and neurological function when compared with nonionic contrast media. It is known, that the organic iodine compounds attenuate x-rays as they pass through the body, thereby allowing the body structures containing iodine to be delineated in contrast to those structures that do not contain iodine. The degree of opacity produced by these compounds is directly proportional to the total amount (concentration and volume) of the iodinated contrast agent in the path of the x-rays. Thus, after intravascular administration, iodixanol makes opaque those internal structures in its path of flow, allowing their visualization until significant hemodilution and elimination occur.

Risperidone, a benzisoxazole derivative, is an atypical antipsychotic drug with high affinity for 5-hydrotryptamine (5-HT) and dopamine D2 receptors. It is FDA approved for the treatment of schizophrenia, bipolar mania, irritability associated with autistic disorder. Carbamazepine and other enzyme inducers decrease plasma concentrations of risperidone. Vice versa, Fluoxetine, paroxetine, and other CYP 2D6 enzyme inhibitors increase plasma concentrations of risperidone. Common adverse reactions include increased mortality in elderly patients with dementia-related psychosis, cerebrovascular adverse events, including stroke, in elderly patients with dementia-related psychosis, neuroleptic malignant syndrome, tardive dyskinesia , metabolic Changes (hyperglycemia and diabetes mellitus, dyslipidemia, weight gain), hyperprolactinemia, orthostatic hypotension, leukopenia, neutropenia, agranulocytosis, potential for cognitive and motor impairment, seizures, dysphagia, priapism, disruption of body temperature regulation.

Fluvastatin is an antilipemic agent that competitively inhibits hydroxymethylglutaryl-coenzyme A (HMG-CoA) reductase. Fluvastatin is marketed under the trade names Lescol, Canef, Vastin. LESCOL/LESCOL XL is an HMG-CoA reductase inhibitor (statin) indicated as an adjunctive therapy to diet to: Reduce elevated TC, LDL-C, Apo B, and TG, and to increase HDL-C in adult patients with primary hypercholesterolemia and mixed dyslipidemia Reduce elevated TC, LDL-C, and Apo B levels in boys and post-menarchal girls, 10 to 16 years of age, with heterozygous familial hypercholesterolemia after failing an adequate trial of diet therapy Reduce the risk of undergoing revascularization procedures in patients with clinically evident CHD Slow the progression of atherosclerosis in patients with CHD. Fluvastatin selectively and competitively inhibits the hepatic enzyme hydroxymethylglutaryl-coenzyme A (HMG-CoA) reductase. HMG-CoA reductase is responsible for converting HMG-CoA to mevalonate, the rate-limiting step in cholesterol biosynthesis. Inhibition results in a decrease in hepatic cholesterol levels which stimulates the synthesis of LDL receptors and increases hepatic uptake of LDL cholesterol. The end result is decreased levels of plasma total and LDL cholesterol.

Rimantadine (INN, sold under the trade name Flumadine) is an orally administered antiviral drug used to treat, and in rare cases prevent, influenzavirus A infection. Rimantadine is an M2 ion channel inhibitor which specifically inhibits the replication of influenza A viruses by interfering with the uncoating process of the virus. M2 inhibitors block the ion channel formed by the M2 protein that spans the viral membrane (Hay 1985, Sugrue 1991). The influenza virus enters its host cell by receptor-mediated endocytosis. Thereafter, acidification of the endocytotic vesicles is required for the dissociation of the M1 protein from the ribonucleoprotein complexes. Only then are the ribonucleoprotein particles imported into the nucleus via the nuclear pores. The hydrogen ions needed for acidification pass through the M2 channel. The drug is effective against all influenza A subtypes that have previously caused disease in humans (H1N1, H2N2, and H3N2), but not against influenza B virus because the M2 protein is unique to influenza A viruses. Rimantadine is not active against the avian flu subtype H5N1 strains that have recently caused disease in humans.