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.

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.

Lisinopril is a potent, competitive inhibitor of angiotensin-converting enzyme (ACE). Lisinopril is marketed under the brand name ZESTRIL. ZESTRIL is indicated for the treatment of hypertension. It may be used alone as initial therapy or concomitantly with other classes of antihypertensive agents. It is also indicated as adjunctive therapy in the management of heart failure in patients who are not responding adequately to diuretics and digitalis. Lisinopril inhibits angiotensin-converting enzyme (ACE) in human subjects and animals. ACE is a peptidyl dipeptidase that catalyzes the conversion of angiotensin I to the vasoconstrictor substance, angiotensin II. Angiotensin II also stimulates aldosterone secretion by the adrenal cortex. The beneficial effects of lisinopril in hypertension and heart failure appear to result primarily from suppression of the renin-angiotensin-aldosterone system. Inhibition of ACE results in decreased plasma angiotensin II which leads to decreased vasopressor activity and to decreased aldosterone secretion. While the mechanism through which ZESTRIL lowers blood pressure is believed to be primarily suppression of the renin-angiotensin-aldosterone system, ZESTRIL is antihypertensive even in patients with low-renin hypertension.

Alfentanil is an opioid analgesic with a rapid onset of action. Alfentanil interacts predominately with the opioid mu-receptor. These mu-binding sites are discretely distributed in the human brain, spinal cord, and other tissues. In clinical settings, alfentanil exerts its principal pharmacologic effects on the central nervous system. Its primary actions of therapeutic value are analgesia and sedation. Alfentanil may increase the patient's tolerance for pain and decrease the perception of suffering, although the presence of the pain itself may still be recognized. In addition to analgesia, alterations in mood, euphoria and dysphoria, and drowsiness commonly occur. Alfentanil depresses the respiratory centers, depresses the cough reflex, and constricts the pupils. Alfentanil, marketed under the trade name Alfenta, Rapifen in Australia is indicated for the management of postoperative pain and the maintenance of general anesthesia.

Nabilone is a synthetic cannabinoid approved under the brand name cesamet for treatment of severe nausea and vomiting associated with cancer chemotherapy. Nabilone is an orally active which, like other cannabinoids, has complex effects on the central nervous system (CNS). It has been suggested that the antiemetic effect of nabilone is caused by interaction with the cannabinoid receptor system, i.e. the CB (1) receptor, which has been discovered in neural tissues.

Enalapril (marketed as Vasotec in the US, Enaladex and Renitec in some other countries) is an angiotensin-converting-enzyme (ACE) inhibitor used in the treatment of hypertension, diabetic nephropathy, and some types of chronic heart failure. Enalapril, after hydrolysis to enalaprilat, inhibits angiotensin-converting enzyme (ACE) in human subjects and animals. ACE is a peptidyl dipeptidase that catalyzes the conversion of angiotensin I to the vasoconstrictor substance, angiotensin II. Angiotensin II also stimulates aldosterone secretion by the adrenal cortex. The beneficial effects of enalapril in hypertension and heart failure appear to result primarily from suppression of the renin-angiotensin-aldosterone system. Inhibition of ACE results in decreased plasma angiotensin II, which leads to decreased vasopressor activity and to decrease aldosterone secretion.

Sufentanil is a synthetic opioid analgesic. Sufentanil interacts predominately with the opioid mu-receptor. These mu-binding sites are discretely distributed in the human brain, spinal cord, and other tissues. In clinical settings, sufentanil exerts its principal pharmacologic effects on the central nervous system. Its primary actions of therapeutic value are analgesia and sedation. Sufentanil may increase the patient's tolerance for pain and decrease the perception of suffering, although the presence of the pain itself may still be recognized. In addition to analgesia, alterations in mood, euphoria and dysphoria, and drowsiness commonly occur. Sufentanil depresses the respiratory centers, depresses the cough reflex, and constricts the pupils. Opiate receptors are coupled with G-protein receptors and function as both positive and negative regulators of synaptic transmission via G-proteins that activate effector proteins. Binding of the opiate stimulates the exchange of GTP for GDP on the G-protein complex. As the effector system is adenylate cyclase and cAMP located at the inner surface of the plasma membrane, opioids decrease intracellular cAMP by inhibiting adenylate cyclase. Subsequently, the release of nociceptive neurotransmitters such as substance P, GABA, dopamine, acetylcholine and noradrenaline is inhibited. Opioids also inhibit the release of vasopressin, somatostatin, insulin and glucagon. Sufentanil's analgesic activity is, most likely, due to its conversion to morphine. Opioids open calcium-dependent inwardly rectifying potassium channels (OP1 receptor agonist). This results in hyperpolarization and reduced neuronal excitability. Sufentanil is used as an analgesic adjunct in anesthesia and as a primary anesthetic drug in procedures requiring assisted ventilation and in the relief of pain.

Indapamide is an antihypertensive and a diuretic. It contains both a polar sulfamoyl chlorobenzamide moiety and a lipid- soluble methylindoline moiety. Indapamide blocks the slow component of delayed rectifier potassium current (IKs) without altering the rapid component (IKr) or the inward rectifier current. Specifically it blocks or antagonizes the action the proteins KCNQ1 and KCNE1. Indapamide is also thought to stimulate the synthesis of the vasodilatory hypotensive prostaglandin PGE2. Indapamide is used for the treatment of hypertension, alone or in combination with other antihypertensive drugs, as well as for the treatment of salt and fluid retention associated with congestive heart failure or edema from pregnancy (appropriate only in the management of edema of pathologic origin during pregnancy when clearly needed). Also used for the management of edema as a result of various causes.

Etoposide (trade name Etopophos) is a semisynthetic derivative of podophyllotoxin that exhibits antitumor activity. It has been in clinical use for more than two decades and remains one of the most highly prescribed anticancer drugs in the world. The primary cytotoxic target for etoposide is topoisomerase II. This ubiquitous enzyme regulates DNA under- and over winding, and removes knots and tangles from the genome by generating transient double-stranded breaks in the double helix. Etoposide kills cells by stabilizing a covalent enzyme-cleaved DNA complex (known as the cleavage complex) that is a transient intermediate in the catalytic cycle of topoisomerase II. The accumulation of cleavage complexes in treated cells leads to the generation of permanent DNA strand breaks, which trigger recombination/repair pathways, mutagenesis, and chromosomal translocations. If these breaks overwhelm the cell, they can initiate death pathways. Thus, etoposide converts topoisomerase II from an essential enzyme to a potent cellular toxin that fragments the genome. Although the topoisomerase II-DNA cleavage complex is an important target for cancer chemotherapy, there also is evidence that topoisomerase II-mediated DNA strand breaks induced by etoposide and other agents can trigger chromosomal translocations that lead to specific types of leukemia. Etopophos (etoposide phosphate) is indicated in the management of the following neoplasms: Refractory Testicular Tumors-and for Small Cell Lung Cancer. The in vitro cytotoxicity observed for etoposide phosphate is significantly less than that seen with etoposide, which is believed due to the necessity for conversion in vivo to the active moiety, etoposide, by dephosphorylation. The mechanism of action is believed to be the same as that of etoposide.

Alclometasone is synthetic glucocorticoid steroid for topical use. Alclometasone dipropionate cream USP and alclometasone dipropionate ointment USP are indicated for the relief of the inflammatory and pruritic manifestations of corticosteroid-responsive dermatoses. It may be used in pediatric patients 1 year of age or older, although the safety and efficacy of drug use for longer than 3 weeks have not been established. Like other topical corticosteroids, alclometasone dipropionate has anti-inflammatory, antipruritic, and vasoconstrictive properties. The mechanism of the anti-inflammatory activity of the topical steroids, in general, is unclear. However, corticosteroids are thought to act by the induction of phospholipase A2inhibitory proteins, collectively called lipocortins. It is postulated that these proteins control the biosynthesis of potent mediators of inflammation such as prostaglandins and leukotrienes by inhibiting the release of their common precursor, arachidonic acid. Arachidonic acid is released from membrane phospholipids by phospholipase A2. Alclometasone initially binds the corticosteroid receptor. This complex migrates to the nucleus where it binds to different glucocorticoid response elements on the DNA. This in turn enhances and represses various genes, especially those involved in inflammatory pathways.