Ertapenem is a carbapenem antibiotic marketed by Merck as Invanz. The bactericidal activity of ertapenem results from the inhibition of cell wall synthesis and is mediated through ertapenem binding to penicillin binding proteins (PBPs). In Escherichia coli, it has strong affinity toward PBPs 1a, 1b, 2, 3, 4 and 5 with preference for PBPs 2 and 3. Ertapenem has been designed to be effective against Gram-negative and Gram-positive bacteria. The most common drug-related adverse experiences in patients treated with INVANZ, including those who were switched to therapy with an oral antimicrobial, were diarrhea (5.5%), infused vein complication (3.7%), nausea (3.1%), headache (2.2%), vaginitis in females (2.1%), phlebitis/thrombophlebitis (1.3%), and vomiting (1.1%). The coadministration with probenecid to extend the half-life of ertapenem is not recommended.

Frovatriptan succinate (trade name Frova) is a selective 5-hydroxytryptamine1 (5-HT1B/1D) receptor subtype agonist, and is used for the treatment of migraine attacks with or without aura in adults. Frovatriptan has no significant effects on GABAA mediated channel activity and has no significant affinity for benzodiazepine binding sites. Frovatriptan is believed to act on extracerebral, intracranial arteries and to inhibit excessive dilation of these vessels in migraine. Serious but rare cardiac events have been reported in patients with risk factors predictive of coronary artery disease (CAD). These include coronary artery vasospasm, transient myocardial ischemia, myocardial infarction, ventricular tachycardia and ventricular fibrillation.

Pimecrolimus, an ascomycin macrolactam derivative, is an inhibitor of T-cell and mast-cell activation, developed and launched by Novartis for the potential treatment of psoriasis and allergic, irritant and atopic dermatitis. The topical formulation had been launched in the US by February 2002 for mild-to-moderate atopic dermatitis in patients aged two years and older. Pimecrolimus is an immunomodulating agent. The mechanism of action of pimecrolimus in atopic dermatitis is not known. While the following have been observed, the clinical significance of these observations in atopic dermatitis is not known. It has been demonstrated that pimecrolimus binds with high affinity to macrophilin-12 (FKBP-12) and inhibits the calcium dependent phosphatase, calcineurin. Therefore, it inhibits T cell activation by blocking the transcription of early cytokines. In particular, pimecrolimus inhibits at nanomolar concentrations Interleukin-2 and interferon gamma (Th1-type) and Interleukin-4 and Interleukin-10 (Th2-type) cytokine synthesis in human T-cells. In addition, pimecrolimus prevents the release of inflammatory cytokines and mediators from mast cells in vitro after stimulation by antigen/IgE. Following the administration of a single oral radiolabeled dose of pimecrolimus numerous circulating O-demethylation metabolites were seen. Studies with human liver microsomes indicate that pimecrolimus is metabolized in vitro by the CYP3A sub-family of metabolizing enzymes. No evidence of skin mediated drug metabolism was identified in vivo using the minipig or in vitro using stripped human skin.

Almotriptan is a triptan drug for the treatment of migraine headaches. Almotriptan is marketed under the trade name Axert. Almotriptan is used for treating acute migraine headaches with or without aura (eg, dark spots, flashing lights, wavy lines). Almotriptan binds with high affinity to 5-HT1D, 5-HT1B, and 5-HT1F receptors. Almotriptan has weak affinity for 5-HT1A and 5-HT7 receptors, but has no significant affinity or pharmacological activity at 5-HT2, 5-HT3, 5-HT4, 5-HT6; alpha or beta adrenergic; adenosine (A1, A2); angiotensin (AT1, AT2); dopamine (D1, D2); endothelin (ETA, ETB); or tachykinin (NK1, NK2, NK3) binding sites.

Cevimeline is a cholinergic agonist, which binds to muscarinic receptors. Muscarinic agonists in sufficient dosage can increase secretion of exocrine glands, such as salivary and sweat glands and increase tone of the smooth muscle in the gastrointestinal and urinary tracts. Cevimeline is indicated for the treatment of symptoms of dry mouth in patients with Sjögren’s Syndrome. Known side effects include nausea, vomiting, diarrhea, excessive sweating, rash, headache, runny nose, cough, drowsiness, hot flashes, blurred vision, and difficulty sleeping. Cevimeline should be administered with caution to patients taking beta adrenergic antagonists, because of the possibility of conduction disturbances. Drugs with para-sympathomimetic effects administered concurrently with cevimeline can be expected to have additive effects. Cevimeline might interfere with desirable antimuscarinic effects of drugs used concomitantly.

Pantoprazole is a proton pump inhibitor that inhibits gastric acid secretion and used for short-term treatment of erosive esophagitis associated with gastroesophageal reflux disease. Pantoprazole suppresses the final step in gastric acid production by covalently binding to the (H+, K+)-ATPase enzyme system at the secretory surface of the gastric parietal cell. This effect leads to inhibition of both basal and stimulated gastric acid secretion, irrespective of the stimulus. The binding to the (H+, K+)-ATPase results in a duration of antisecretory effect that persists longer than 24 hours. Pantoprazole is used for short-term treatment of erosion and ulceration of the esophagus for adults and pediatric patients 5 years of age and older caused by gastroesophageal reflux disease. It can be used as a maintenance therapy for long-term use after initial response is obtained, but there have not been any controlled studies about the use of pantoprazole past a duration of 12 months. Pantoprazole may also be used in combination with antibiotics to treat ulcers caused by Helicobacter pylori. Use of pantoprazole may increase the chance of developing infections such as pneumonia, particularly in hospitalized patients.

Argatroban is a synthetic direct thrombin inhibitor derived from L-arginine. Argatroban is a direct thrombin inhibitor that reversibly binds to the thrombin active site. Argatroban does not require the co-factor antithrombin III for antithrombotic activity. Argatroban exerts its anticoagulant effects by inhibiting thrombin-catalyzed or -induced reactions, including fibrin formation; activation of coagulation factors V, VIII, and XIII; protein C; and platelet aggregation. Argatroban is highly selective for thrombin with an inhibitory constant (Ki) of 0.04 µM. At therapeutic concentrations, Argatroban has little or no effect on related serine proteases (trypsin, factor Xa, plasmin, and kallikrein). Argatroban is capable of inhibiting the action of both free and clot-associated thrombin. Argatroban is indicated as an anticoagulant for prophylaxis or treatment of thrombosis in patients with heparin-induced thrombocytopenia. Argatroban is indicated as an anticoagulant in patients with or at risk for heparin-induced thrombocytopenia undergoing percutaneous coronary intervention (PCI).

Alosetron, marketed under the brand name Lotronex, is a 5-HT3 antagonist used for the management of severe diarrhea-predominant irritable bowel syndrome (IBS) in women only. Alosetron is a potent and selective 5-HT3 receptor antagonist. 5-HT3 receptors are nonselective cation channels that are extensively distributed on enteric neurons in the human gastrointestinal tract, as well as other peripheral and central locations. Activation of these channels and the resulting neuronal depolarization affect the regulation of visceral pain, colonic transit and gastrointestinal secretions, processes that relate to the pathophysiology of irritable bowel syndrome (IBS). 5-HT3 receptor antagonists such as alosetron inhibit activation of non-selective cation channels which results in the modulation of the enteric nervous system. Alosetron is used for the treating women with severe irritable bowel syndrome (IBS) accompanied by severe diarrhea (usually lasting for 6 months or more). It is only prescribed to women who do not respond to other medicines and is not to be used by women whose main IBS problem is constipation.

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.

Naratriptan (trade names include Amerge and Naramig) is a triptan drug marketed by GlaxoSmithKline and is used for the treatment of migraine headaches.Naratriptan is a selective agonist of serotonin (5-hydroxytryptamine; 5-HT) type 1B and 1D receptors. It is structurally and pharmacologically related to other selective 5-HT1B/1D receptor agonist. Naratriptan has only a weak affinity for 5-HT1A, 5-HT5A, and 5-HT7 receptors and no significant affinity or pharmacological activity at 5-HT2, 5-HT3 or 5-HT4 receptor subtypes or at alpha1-, alpha2-, or beta-adrenergic, dopamine1,; dopamine2; muscarinic, or benzodiazepine receptors. This action in humans correlates with the relief of migraine headache. In addition to causing vasoconstriction, experimental data from animal studies show that Naratriptan also activates 5-HT1 receptors on peripheral terminals of the trigeminal nerve innervating cranial blood vessels, which may also contribute to the antimigrainous effect of Naratriptan in humans.Three distinct pharmacological actions have been implicated in the antimigraine effect of the triptans: (1) stimulation of presynaptic 5-HT1D receptors, which serves to inhibit both dural vasodilation and inflammation; (2) direct inhibition of trigeminal nuclei cell excitability via 5-HT1B/1D receptor agonism in the brainstem and (3) vasoconstriction of meningeal, dural, cerebral or pial vessels as a result of vascular 5-HT1B receptor agonism.