Amiodarone is an antiarrhythmic with mainly class III properties, but it possesses electrophysiologic characteristics of all four Vaughan Williams classes. Like class I drugs, amiodarone blocks sodium channels at rapid pacing frequencies, and like class II drugs, amiodarone exerts a noncompetitive antisympathetic action. In addition to blocking sodium channels, amiodarone blocks myocardial potassium channels, which contributes to slowing of conduction and prolongation of refractoriness. It is indicated for initiation of treatment and prophylaxis of frequently recurring ventricular fibrillation and hemodynamically unstable ventricular tachycardia in patients refractory to other therapy. The most common adverse reactions (1-2%) leading to discontinuation of intravenous amiodarone therapy are hypotension, asystole/cardiac arrest/pulseless electrical activity, VT, and cardiogenic shock. Other important adverse reactions are, torsade de pointes (TdP), congestive heart failure, and liver function test abnormalities. Fluoroquinolones, macrolide antibiotics, and azoles are known to cause QTc prolongation. There have been reports of QTc prolongation, with or without TdP, in patients taking amiodarone when fluoroquinolones, macrolide antibiotics, or azoles were administered concomitantly. Since amiodarone is a substrate for CYP3A and CYP2C8, drugs/substances that inhibit these isoenzymes may decrease the metabolism and increase serum concentration of amiodarone.

Quazepam is indicated for the treatment of insomnia characterized by difficulty in falling asleep, frequent nocturnal awakenings, and/or early morning awakenings. Quazepam interact preferentially with the benzodiazepine-1 (BZ1) receptors. Most common adverse reactions (>1%): drowsiness, headache, fatigue, dizziness, dry mouth, dyspepsia. Downward of CAN depressant dose adjustment may be necessary due to additive effects.

Ribavirin is a synthetic nucleoside analogue, which was first discovered and developed in 1970 by researchers from the International Chemical & Nuclear Corporation (ICN), today known as Valeant Pharmaceuticals. Ribavirin was initially approved for use in humans to treat pediatric respiratory syncytial virus infections (RSV). In cell cultures the inhibitory activity of ribavirin for RSV is selective. The mechanism of action is unknown. Reversal of the in vitro antiviral activity by guanosine or xanthosine suggests ribavirin may act as an analogue of these cellular metabolites. There were no other significant advancements in the treatment of hepatitis C until 1998, when the combination of ribavirin and interferon-alpha gained approval. Clinically, ribavirin showed a small, additive antiviral effect in combination with interferon, but its main effect was dose-dependent prevention of virological relapse. The mechanism by which the combination of ribavirin and an interferon product exerts its effects against the hepatitis C virus has not been fully established. However, it could be thorough the inhibition of inosine monophosphate dehydrogenase (IMPDH), which is the key step in de novo guanine synthesis, a requirement for viral replication.

Glyburide, a second-generation sulfonylurea antidiabetic agent, lowers blood glucose acutely by stimulating the release of insulin from the pancreas, an effect dependent upon functioning beta cells in the pancreatic islets. With chronic administration in Type II diabetic patients, the blood glucose lowering effect persists despite a gradual decline in the insulin secretory response to the drug. Extrapancreatic effects may be involved in the mechanism of action of oral sulfonyl-urea hypoglycemic drugs. The combination of glibenclamide and metformin may have a synergistic effect, since both agents act to improve glucose tolerance by different but complementary mechanisms. In addition to its blood glucose lowering actions, glyburide produces a mild diuresis by enhancement of renal free water clearance. Glyburide is twice as potent as the related second-generation agent glipizide. Sulfonylureas such as glyburide bind to ATP-sensitive potassium channels on the pancreatic cell surface, reducing potassium conductance and causing depolarization of the membrane. Depolarization stimulates calcium ion influx through voltage-sensitive calcium channels, raising intracellular concentrations of calcium ions, which induces the secretion, or exocytosis, of insulin. Glyburide is indicated as an adjunct to diet to lower the blood glucose in patients with NIDDM whose hyperglycemia cannot be satisfactorily controlled by diet alone. Glyburide is available as a generic, is manufactured by many pharmaceutical companies and is sold in doses of 1.25, 2.5 and 5 mg under many brand names including Gliben-J, Daonil, Diabeta, Euglucon, Gilemal, Glidanil, Glybovin, Glynase, Maninil, Micronase and Semi-Daonil. It is also available in a fixed-dose combination drug with metformin that is sold under various trade names, e.g. Bagomet Plus, Benimet, Glibomet, Gluconorm, Glucored, Glucovance, Metglib and many others.

Ceftriaxone is a broad-spectrum cephalosporin antibiotic with a very long half-life. Ceftriaxone is a bactericidal agent that acts by inhibition of bacterial cell wall synthesis. Ceftriaxone has activity in the presence of some beta-lactamases, both penicillinases and cephalosporinases, of Gram-negative and Gram-positive bacteria. It is approved for the treatment of lower respiratory tract infections, acute bacterial otitis media, skin infections, urinary tract infections, pelvic inflammatory disease, bacterial septicemia, bone and joint infections, intraabdominal infection, meningitis, and surgical prophylaxis. Common adverse reactions include erythema multiforme, Stevens-Johnson syndrome, toxic epidermal necrolysis, pseudomembranous enterocolitis, hemolytic anemia, hypersensitivity reaction, kernicterus, renal failure, and lung injury. Vancomycin, amsacrine, aminoglycosides, and fluconazole are incompatible with Ceftriaxone in admixtures. Precipitation of Ceftriaxone-calcium can occur when Ceftriaxone for Injection is mixed with calcium-containing solutions in the same intravenous administration line.

Glipizide, a second-generation sulfonylurea, is used with diet to lower blood glucose in patients with diabetes mellitus type II. The primary mode of action of glipizide in experimental animals appears to be the stimulation of insulin secretion from the beta cells of pancreatic islet tissue and is thus dependent on functioning beta cells in the pancreatic islets. In humans glipizide appears to lower the blood glucose acutely by stimulating the release of insulin from the pancreas, an effect dependent upon functioning beta cells in the pancreatic islets. In man, stimulation of insulin secretion by glipizide in response to a meal is undoubtedly of major importance. Fasting insulin levels are not elevated even on long-term glipizide administration, but the postprandial insulin response continues to be enhanced after at least 6 months of treatment. Some patients fail to respond initially, or gradually lose their responsiveness to sulfonylurea drugs, including glipizide. Sulfonylureas likely bind to ATP-sensitive potassium-channel receptors on the pancreatic cell surface, reducing potassium conductance and causing depolarization of the membrane. Depolarization stimulates calcium ion influx through voltage-sensitive calcium channels, raising intracellular concentrations of calcium ions, which induces the secretion, or exocytosis, of insulin. Glipizide is used as an adjunct to diet for the control of hyperglycemia and its associated symptomatology in patients with non-insulin-dependent diabetes mellitus (NIDDM; type II), formerly known as maturity-onset diabetes, after an adequate trial of dietary therapy has proved unsatisfactory. Glipizide is marketed by Pfizer under the brand name Glucotrol in the USA, where Pfizer sells Glucotrol in doses of 5 and 10 milligrams and Glucotrol XL (an extended release form of glipizide) in doses of 2.5, 5, and 10 milligrams. Other companies also market glipizide, most commonly extended release tablets of 5 and 10 milligrams.

Ranitidine, a histamine H2-receptor antagonist, is now well established as a potent inhibitor of gastric acid secretion effective in the treatment and prophylaxis of gastrointestinal lesions aggravated by gastric acid secretion.

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.

Alprazolam, a benzodiazepine, is used to treat panic disorder and anxiety disorder. Unlike chlordiazepoxide, clorazepate, and prazepam, alprazolam has a shorter half-life and metabolites with minimal activity. Alprazolam may have significant drug interactions involving the hepatic cytochrome P-450 3A4 isoenzyme. Clinically, all benzodiazepines cause a dose-related central nervous system depressant activity varying from mild impairment of task performance to hypnosis. Unlike other benzodiazepines, alprazolam may also have some antidepressant activity, although clinical evidence of this is lacking. CNS agents of the 1,4 benzodiazepine class presumably exert their effects by binding at stereo specific receptors at several sites within the central nervous system. Their exact mechanism of action is unknown. Benzodiazepines bind nonspecifically to benzodiazepine receptors BNZ1, which mediates sleep, and BNZ2, which affects muscle relaxation, anticonvulsant activity, motor coordination, and memory. As benzodiazepine receptors are thought to be coupled to gamma-aminobutyric acid-A (GABAA) receptors, this enhances the effects of GABA by increasing GABA affinity for the GABA receptor. Binding of the inhibitory neurotransmitter GABA to the site opens the chloride channel, resulting in a hyperpolarized cell membrane that prevents further excitation of the cell.

Praziquantel, marketed as Biltricide, is an anthelmintic used in humans and animals for the treatment of tapeworms and flukes. Specifically, it is effective against schistosoma, Clonorchis sinensis the fish tape worm Diphyllobothrium latum. Praziquantel works by causing severe spasms and paralysis of the worms' muscles. This paralysis is accompanied - and probably caused - by a rapid Ca 2+ influx inside the schistosome. Morphological alterations are another early effect of praziquantel. These morphological alterations are accompanied by an increased exposure of schistosome antigens at the parasite surface. The worms are then either completely destroyed in the intestine or passed in the stool. An interesting quirk of praziquantel is that it is relatively ineffective against juvenile schistosomes. While initially effective, effectiveness against schistosomes decreases until it reaches a minimum at 3-4 weeks. Effectiveness then increases again until it is once again fully effective at 6-7 weeks. Glutathione S-transferase (GST), an essential detoxification enzyme in parasitic helminths, is a major vaccine target and a drug target against schistosomiasis. Schistosome calcium ion channels are currently the only known target of praziquantel. The antibiotic rifampicin decreases plasma concentrations of praziquantel. Carbamazepine and phenytoin are reported to reduce the bioavailability of praziquantel. Chloroquine reduces the bioavailability of praziquantel. The drug cimetidine heightens praziquantel bioavailability.