Desfesoterodine is an active metabolite of antimuscarinic drugs for the treatment of overactive bladder fesoterodine and tolterodine. In contrast to the cytochrome P450 (CYP) 2D6-mediated metabolism of tolterodine, desfesoterodine formation from fesoterodine occurs via ubiquitous nonspecific esterases. Serum levels of the desfesoterodine in humans are generally comparable to those of tolterodine following oral administration of the parent compound. The pharmacological in vitro and in vivo profiles of desfesoterodine are almost identical to those of tolterodin. The potent antimuscarinic action of desfesoterodine on the urinary bladder was confirmed in the in vivo studies and, like tolterodine, desfesoterodine was significantly more potent in inhibiting bladder contractions than salivation in the anaesthetised cat. Desfesoterodine is more potent than tolterodine in vivo. The apparent difference in potency in vivo might be explained by the degree of serum protein binding of the two compounds. The fraction of unbound drug in serum is larger for desfesoterodine than for tolterodine. Desfesoterodine may contribute to the therapeutical action of tolterodine.

Acamprosate was the third medication, after disulfiram and naltrexone, to receive U.S. Food and Drug Administration (FDA) approval for postwithdrawal maintenance of alcohol abstinence. The French pharmaceutical company Laboratoires Meram began clinical development and testing of acamprosate in 1982. From 1982 to 1988, acamprosate was tested for safety and for efficacy as a treatment for alcohol dependence. Based on these studies, in 1989 Laboratoires Meram was granted marketing authorization for acamprosate in France under the trade name Aotal®. Since then, acamprosate has been extensively used and studied throughout Europe and, subsequently, in the United States. Although acamprosate has been used in Europe for more than 20 years, it was not approved by FDA until July 2004. Acamprosate became available for use in the United States in January 2005, under the trade name Campral® Delayed-Release Tablets (Merck Santé, a subsidiary of Merck KGaA, Darmstadt, Germany). Campral is currently marketed in the United States by Forest Pharmaceuticals. The mechanism of action of acamprosate in maintenance of alcohol abstinence is not completely understood. Chronic alcohol exposure is hypothesized to alter the normal balance between neuronal excitation and inhibition. in vitro and in vivo studies in animals have provided evidence to suggest acamprosate may interact with glutamate and GABA neurotransmitter systems centrally, and has led to the hypothesis that acamprosate restores this balance. It seems to inhibit NMDA receptors while activating GABA receptors.

Palonosetron (INN, trade name Aloxi) is a 5-HT3 antagonist used in the prevention and treatment of postoperative and chemotherapy-induced nausea and vomiting (PONV and CINV). Palonosetron is a 5-HT3 receptor antagonist with a strong binding affinity for this receptor and little or no affinity for other receptors. Cancer chemotherapy may be associated with a high incidence of nausea and vomiting, particularly when certain agents, such as cisplatin, are used. 5-HT3 receptors are located on the nerve terminals of the vagus in the periphery and centrally in the chemoreceptor trigger zone of the area postrema. It is thought that chemotherapeutic agents produce nausea and vomiting by releasing serotonin from the enterochromaffin cells of the small intestine and that the released serotonin then activates 5-HT3 receptors located on vagal afferents to initiate the vomiting reflex. Postoperative nausea and vomiting is influenced by multiple patients, surgical and anesthesia-related factors and is triggered by the release of 5-HT in a cascade of neuronal events involving both the central nervous system and the gastrointestinal tract. The 5-HT3 receptor has been demonstrated to selectively participate in the emetic response. The most common adverse effects are a headache, which occurs in 4–11% of patients, and constipation in up to 6% of patients. In less than 1% of patients, other gastrointestinal disorders occur, as well as sleeplessness, first- and second-degree atrioventricular block, muscle pain and shortness of breath. Palonosetron is similarly well tolerated as other sections, and slightly less than placebo.

Zoledronic acid (Reclast, Aclasta, Zometa) is an intravenous, highly potent amino-bisphosphonate approved worldwide, including in the USA, EU and Japan for use in patients with primary or secondary osteoporosis or low bone mass (approved indications vary between countries). Its high affinity to and long half-life in bone, and long duration of action allow for once-yearly administration, which has the potential to improve adherence to therapy. Zoledronic acid once yearly for up to 3 years improved bone mineral density (BMD) at several skeletal sites, reduced fracture risk and bone turnover, and/or preserved bone structure and mass relative to placebo in clinical studies in patients with primary or secondary osteoporosis. While additional benefits were seen when treatment was continued for up to 6 years, as evidenced by a reduced risk of vertebral fractures and higher BMD relative to 3 years’ therapy, there was the minimal advantage of treatment beyond 6 years. Therefore, in patients with low fracture risk, treatment discontinuation should be considered after approximately 5 years’ therapy. Zoledronic acid administered annually or once in 2 years was also effective in preventing bone loss in patients with low bone mass. Zoledronic acid was generally well tolerated, with the most common adverse events (AEs) being transient, mild-to-moderate post-infusion symptoms, which decreased with subsequent infusions.

Cetrorelix is a synthetic decapeptide with gonadotropin-releasing hormone (GnRH) antagonistic activity. GnRH induces the production and release of luteinizing hormone (LH) and follicle stimulating hormone (FSH) from the gonadotrophic cells of the anterior pituitary. Due to a positive estradiol (E2) feedback at midcycle, GnRH liberation is enhanced resulting in an LH-surge. This LH-surge induces the ovulation of the dominant follicle, resumption of oocyte meiosis and subsequently luteinization as indicated by rising progesterone levels. Cetrorelix competes with natural GnRH for binding to membrane receptors on pituitary cells and thus controls the release of LH and FSH in a dose-dependent manner. Cetrorelix binds to the gonadotropin releasing hormone receptor and acts as a potent inhibitor of gonadotropin secretion. It competes with natural GnRH for binding to membrane receptors on pituitary cells and thus controls the release of LH and FSH in a dose-dependent manner. Cetrorelix is marketed primarily under the brand name Cetrotide. Cetrotide (cetrorelix acetate for injection) is indicated for the inhibition of premature LH surges in women undergoing controlled ovarian stimulation.

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.

Citalopram (brand names: Celexa, Cipramil, and others) is an antidepressant drug of the selective serotonin reuptake inhibitor (SSRI) class. It has U.S. Food and Drug Administration approval to treat major depression,[2]which it received in 1998, and is prescribed off-label for other conditions. In Australia, the UK, Germany, Portugal, Poland, and most European countries, it is licensed for depressive episodes and panic disorder with or without agoraphobia. In Spain, it is also used for obsessive-compulsive disorder. Citalopram HBr is a racemic bicyclic phthalane derivative designated (±)-1-(3-dimethylaminopropyl)-1-(4-fluorophenyl)-1,3-dihydroisobenzofuran-5carbonitrile, HBr. The mechanism of action of citalopram HBr as an antidepressant is presumed to be linked to potentiation of serotonergic activity in the central nervous system (CNS) resulting from its inhibition of CNS neuronal reuptake of serotonin (5-HT). In vitro and in vivo studies in animals suggest that citalopram is a highly selective serotonin reuptake inhibitor (SSRI) with minimal effects on norepinephrine (NE) and dopamine (DA) neuronal reuptake. The single-and multiple-dose pharmacokinetics of citalopram are linear and dose-proportional in a dose range of 10-60 mg/day. Biotransformation of citalopram is mainly hepatic, with a mean terminal half-life of about 35 hours.

Montelukast (SINGULAIR®) is a selective and orally active leukotriene D4 (LTD4) receptor antagonist that inhibits the cysteinyl leukotriene CysLT1 receptor. It is indicated for the prophylaxis and chronic treatment of asthma, for prevention of exercise-induced bronchoconstriction, and for the relief of symptoms of seasonal allergic rhinitis. LTD4 is a product of arachidonic acid metabolism and is released from various cells, including mast cells and eosinophils. This eicosanoid binds to CysLT1 receptor found in the human airway (including airway smooth muscle cells and airway macrophages) and on other pro-inflammatory cells (including eosinophils and certain myeloid stem cells). Cysteinyl leukotriene receptors (CysLTs) have been correlated with the pathophysiology of asthma and allergic rhinitis. In asthma, leukotriene-mediated effects include airway edema, smooth muscle contraction, and altered cellular activity associated with the inflammatory process. In allergic rhinitis, CysLTs are released from the nasal mucosa after allergen exposure during both earlyand late-phase reactions and are associated with symptoms of allergic rhinitis. Montelukast (SINGULAIR®) binds with high affinity and selectivity to the CysLT1 (in preference to other pharmacologically important airway receptors, such as the prostanoid, cholinergic, or beta-adrenergic receptor). It inhibits physiologic actions of LTD4 at the CysLT1 receptor without any agonist activity.

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.

Olopatadine is an antihistamine (as well as anticholinergic and mast cell stabilizer) used to treat itching associated with allergic conjunctivitis (eye allergies). Olopatadine is a selective histamine H1 antagonist that binds to the histamine H1 receptor. This blocks the action of endogenous histamine, which subsequently leads to temporary relief of the negative symptoms brought on by histamine. Olopatadine is devoid of effects on alpha-adrenergic, dopamine and muscarinic type 1 and 2 receptors. Some known side effects include a headache (7% of occurrence), eye burning and/or stinging (5%), blurred vision, dry eyes, foreign body sensation, hyperemia, keratitis, eyelid edema, pruritus, asthenia, sore throat (pharyngitis), rhinitis, sinusitis, and taste perversion.