Dolasetron is an antinauseant and antiemetic agent, which is approved as a mesylate salt under the brand name anzement for the prevention of nausea and vomiting associated with moderately emetogenic cancer chemotherapy, including initial and repeat courses; and for the prevention of postoperative nausea and vomiting. Dolasetron is a highly specific and selective serotonin 5-HT3 receptor antagonist. The serotonin 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 efferents to initiate the vomiting reflex. This drug is not shown to have activity at other known serotonin receptors, and has low affinity for dopamine receptors. Dolasetron mesilate is rapidly reduced by carbonyl reductase to form its major pharmacologically active metabolite reduced dolasetron. In addition dolasetron was in the phase III clinical trials for the investigation, that intravenous using of dolasetron mesilate reduces pain intensity in patients with fibromyalgia.

Sparfloxacin is a synthetic fluoroquinolone broad-spectrum antimicrobial agent in the same class as ofloxacin and norfloxacin. Sparfloxacin has in vitro activity against a wide range of gram-negative and gram-positive microorganisms. Sparfloxacin exerts its antibacterial activity by inhibiting DNA gyrase, a bacterial topoisomerase. DNA gyrase is an essential enzyme which controls DNA topology and assists in DNA replication, repair, deactivation, and transcription. Quinolones differ in chemical structure and mode of action from (beta)-lactam antibiotics. Quinolones may, therefore, be active against bacteria resistant to (beta)-lactam antibiotics. Although cross-resistance has been observed between sparfloxacin and other fluoroquinolones, some microorganisms resistant to other fluoroquinolones may be susceptible to sparfloxacin. In vitro tests show that the combination of sparfloxacin and rifampin is antagonistic against Staphylococcus aureus. The bactericidal action of sparfloxacin results from inhibition of the enzymes topoisomerase II (DNA gyrase) and topoisomerase IV, which are required for bacterial DNA replication, transcription, repair, and recombination. Sparfloxacin is used for the treatment of adults with the following infections caused by susceptible strains microorganisms: community-acquired pneumonia (caused by Chlamydia pneumoniae, Haemophilus influenzae, Haemophilus parainfluenzae, Moraxella catarrhalis, Mycoplasma pneumoniae, or Streptococcus pneumoniae) and acute bacterial exacerbations of chronic bronchitis (caused by Chlamydia pneumoniae, Enterobacter cloacae, Haemophilus influenzae, Haemophilus parainfluenzae, Klebsiella pneumoniae, Moraxella catarrhalis,Staphylococcus aureus, or Streptococcus pneumoniae). Sparfloxacin has trade names Spacin in Bangladesh, Zagam and Zagam Respipac. Zagam is no longer available in the United States.

Salsalate is a dimer of salicylic acid. Upon administration, it is metabolically hydrolyzed to salicylic acid. Salsalate is is a nonsteroidal anti-inflammatory agent for oral administration for treatment of rheumatoid arthritis, osteoarthritis and related rheumatoid disorders. In addition, salsalate is investigated for treatment of type 2 diabetes.

Saquinavir (brand names Invirase and Fortovase) is an antiretroviral drug used together with other medications to treat or prevent HIV/AIDS. Saquinavir is an inhibitor of HIV protease. HIV protease is an enzyme required for the proteolytic cleavage of viral polyprotein precursors into individual functional proteins found in infectious HIV. Saquinavir is a peptide-like substrate analog that binds to the protease active site and inhibits the activity of the enzyme. Saquinavir inhibition prevents cleavage of the viral polyproteins resulting in the formation of immature noninfectious virus particles. The most frequent adverse events with saquinavir in either formulation are mild gastrointestinal symptoms, including diarrhea, nausea, loose stools & abdominal discomfort. Invirase is better tolerated than Fortovase.

Cisapride is chemically related to metoclopramide, but unlike metoclopramide, it does not cross the blood-brain barrier or have antidopaminergic effects. Cisapride is a serotonin-4 (5-HT4) receptor agonist. Cisapride was indicated for the symptomatic treatment of adult patients with nocturnal heartburn due to gastroesophageal reflux disease. The Food and Drug Administration (FDA) in America stopped the marketing of cisapride as of 14th July 2000. They had received at least 341 reports of heart rhythm abnormalities and these led to 80 deaths. Other reported adverse effects are: headache, diarrhea, abdominal pain, nausea, constipation. Cisapride for animals has been found helpful in some cases of megaesophagus and is a common treatment for feline megacolon. Clarithromycin, erythromycin, and troleandomycin markedly inhibit the metabolism of cisapride. Concurrent administration of certain anticholinergic compounds, such as belladonna alkaloids and dicyclomine, would be expected to compromise the beneficial effects of cisapride.

Cisapride is chemically related to metoclopramide, but unlike metoclopramide, it does not cross the blood-brain barrier or have antidopaminergic effects. Cisapride is a serotonin-4 (5-HT4) receptor agonist. Cisapride was indicated for the symptomatic treatment of adult patients with nocturnal heartburn due to gastroesophageal reflux disease. The Food and Drug Administration (FDA) in America stopped the marketing of cisapride as of 14th July 2000. They had received at least 341 reports of heart rhythm abnormalities and these led to 80 deaths. Other reported adverse effects are: headache, diarrhea, abdominal pain, nausea, constipation. Cisapride for animals has been found helpful in some cases of megaesophagus and is a common treatment for feline megacolon. Clarithromycin, erythromycin, and troleandomycin markedly inhibit the metabolism of cisapride. Concurrent administration of certain anticholinergic compounds, such as belladonna alkaloids and dicyclomine, would be expected to compromise the beneficial effects of cisapride.

Tacrine is a parasympathomimetic- a reversible cholinesterase inhibitor that is indicated for the treatment of mild to moderate dementia of the Alzheimer's type. An early pathophysiological feature of Alzheimer's disease that is associated with memory loss and cognitive deficits is a deficiency of acetylcholine as a result of selective loss of cholinergic neurons in the cerebral cortex, nucleus basalis, and hippocampus. Tacrine is postulated to exert its therapeutic effect by enhancing cholinergic function. This is accomplished by increasing the concentration of acetylcholine at cholinergic synapses through reversible inhibition of its hydrolysis by acetylcholinesterase. If this proposed mechanism of action is correct, tacrine's effect may lessen as the disease progresses and fewer cholinergic neurons remain functionally intact. There is no evidence that tacrine alters the course of the underlying dementing process. The mechanism of tacrine is not fully known, but it is suggested that the drug is an anticholinesterase agent which reversibly binds with and inactivates cholinesterases. This inhibits the hydrolysis of acetylcholine released from functioning cholinergic neurons, thus leading to an accumulation of acetylcholine at cholinergic synapses. The result is a prolonged effect of acetylcholine. is used for the palliative treatment of mild to moderate dementia of the Alzheimer's type. Tacrine was marketed under the trade name Cognex. Because of its liver toxicity and attendant requirement for monitoring liver function, tacrine prescriptions dropped after other acetylcholinesterase inhibitors were introduced, and its use has been largely discontinued.

Tacrine is a parasympathomimetic- a reversible cholinesterase inhibitor that is indicated for the treatment of mild to moderate dementia of the Alzheimer's type. An early pathophysiological feature of Alzheimer's disease that is associated with memory loss and cognitive deficits is a deficiency of acetylcholine as a result of selective loss of cholinergic neurons in the cerebral cortex, nucleus basalis, and hippocampus. Tacrine is postulated to exert its therapeutic effect by enhancing cholinergic function. This is accomplished by increasing the concentration of acetylcholine at cholinergic synapses through reversible inhibition of its hydrolysis by acetylcholinesterase. If this proposed mechanism of action is correct, tacrine's effect may lessen as the disease progresses and fewer cholinergic neurons remain functionally intact. There is no evidence that tacrine alters the course of the underlying dementing process. The mechanism of tacrine is not fully known, but it is suggested that the drug is an anticholinesterase agent which reversibly binds with and inactivates cholinesterases. This inhibits the hydrolysis of acetylcholine released from functioning cholinergic neurons, thus leading to an accumulation of acetylcholine at cholinergic synapses. The result is a prolonged effect of acetylcholine. is used for the palliative treatment of mild to moderate dementia of the Alzheimer's type. Tacrine was marketed under the trade name Cognex. Because of its liver toxicity and attendant requirement for monitoring liver function, tacrine prescriptions dropped after other acetylcholinesterase inhibitors were introduced, and its use has been largely discontinued.

Lomefloxacin hydrochloride (marketed under the following brand names in English speaking countries Maxaquin, Okacyn, Uniquin) is a fluoroquinolone antibiotic used to treat bacterial infections. It is used to treat chronic bronchitis, as well as complicated and uncomplicated urinary tract infections. It is also used as a prophylactic or preventative treatment to prevent urinary tract infections in patients undergoing transrectal or transurethral surgical procedures. Flouroquinolones such as lomefloxacin possess excellent activity against gram-negative aerobic bacteria such as E.coli and Neisseria gonorrhoea as well as gram-positive bacteria including S. pneumoniae and Staphylococcus aureus. They also posses effective activity against shigella, salmonella, campylobacter, gonococcal organisms, and multi drug resistant pseudomonas and enterobacter. Lomefloxacin is a bactericidal fluoroquinolone agent with activity against a wide range of gram-negative and gram-positive organisms. The bactericidal action of lomefloxacin results from interference with the activity of the bacterial enzymes DNA gyrase and topoisomerase IV, which are needed for the transcription and replication of bacterial DNA. DNA gyrase appears to be the primary quinolone target for gram-negative bacteria. Topoisomerase IV appears to be the preferential target in gram-positive organisms. Interference with these two topoisomerases results in strand breakage of the bacterial chromosome, supercoiling, and resealing. As a result DNA replication and transcription is inhibited.

Halofantrine is a blood schizonticidal antimalarial agent with no apparent action on the sporozoite, gametocyte or hepatic stages of the infection. It is used only to treat but not to prevent malaria. Has been marketed by GlaxoSmithKline as HALFAN (halofantrine hydrochloride) in 250 mg tablets indicated for the treatment of adults who can tolerate oral medication and who have mild to moderate malaria (equal to or less than 100,000 parasites/mm3) caused by Plasmodium falciparum or Plasmodium vivax. Among side effects is cardiac arrhythmia. It belongs to the phenanthrene class of compounds that includes quinine and lumefantrine. It was reported that halofantrine binds to hematin in vitro (crystal structure of the complex) and to to plasmpesin, a haemoglobin degrading enzyme unique to the malarial parasites.