Penciclovir (DENAVIR®) is a synthetic acyclic guanine derivative with antiviral activity, mainly used to treat infections from herpes simplex virus (HSV) types 1 and 2. In cells infected with HSV-1 or HSV-2, the viral thymidine kinase phosphorylates penciclovir to a monophosphate form that, in turn, is converted by cellular kinases to the active form penciclovir triphosphate. Biochemical studies demonstrate that penciclovir triphosphate inhibits HSV polymerase competitively with deoxyguanosine triphosphate. Consequently, herpes viral DNA synthesis and, therefore, replication are selectively inhibited. Famciclovir (FAMVIR®) is a prodrug form of penciclovir with improved oral bioavailability.

Fenofibrate is a drug of the fibrate class. It is mainly used to reduce cholesterol levels in people at risk of cardiovascular disease. It’s used as adjunctive therapy to diet to reduce elevated LDL-C, Total-C,Triglycerides and Apo B, and to increase HDL-C in adult patients with primary hypercholesterolemia or mixed dyslipidemia (Fredrickson Types IIa and IIb). Fenofibrate is a fibric acid derivative, a prodrug comprising fenofibric acid linked to an isopropyl ester. Fenofibrate is rapidly hydrolyzed after oral ingestion to its pharmacologically active form, fenofibric acid. The effects of fenofibric acid seen in clinical practice have been explained in vivo in transgenic mice and in vitro in human hepatocyte cultures by the activation of peroxisome proliferator activated receptor α (PPARα). It lowers lipid levels by activating peroxisome proliferator-activated receptor alpha (PPARα). PPARα activates lipoprotein lipase and reduces apoprotein CIII (an inhibitor of lipoprotein lipase activity), which increases lipolysis and elimination of triglyceride-rich particles from plasma. The resulting fall in triglycerides produces an alteration in the size and composition of LDL from small, dense particles (which are thought to be atherogenic due to their susceptibility to oxidation), to large buoyant particles. These larger particles have a greater affinity for cholesterol receptors and are catabolized rapidly. PPARα also increases apoproteins AI and AII, reduces VLDL- and LDL-containing apoprotein B, and increases HDL-containing apoprotein AI and AII.Fenofibrate also reduces serum uric acid levels in hyperuricemic and normal individuals by increasing the urinary excretion of uric acid. Fenofibrate also has an off-label use as uricosuric therapy in people who have gout.

7Z-Calcipotriol is an isomeric impurity in vitamin D analog calcipotriol. Synthesis of 7Z-Calcipotriol was disclosed by Japanese company Kuraray Co in a patent application JP 06316558.

Butenafine is a synthetic antifungal agent that is structurally and pharmacologically related to allylamine antifungals. The exact mechanism of action has not been established, but it is suggested that butenafine's antifungal activity is exerted through the alteration of cellular membranes, which results in increased membrane permeability, and growth inhibition. Butenafine is mainly active against dermatophytes and has superior fungicidal activity against this group of fungi when compared to that of terbinafine, naftifine, tolnaftate, clotrimazole, and bifonazole. It is also active against Candida albicans and this activity is superior to that of terbinafine and naftifine. Butenafine also generates low MICs for Cryptococcus neoformans and Aspergillus spp. as well. Butenafine hydrochloride is marketed under the trade names Mentax, Butop (India) and is the active ingredient in Lotrimin Ultra. MENTAX Cream, 1%, is indicated for the topical treatment of tinea (pityriasis) versicolor due to Malassezia furfur (formerly Pityrosporum orbiculare). Although the mechanism of action has not been fully established, it has been suggested that butenafine, like allylamines, interferes with sterol biosynthesis (especially ergosterol) by inhibiting squalene monooxygenase, an enzyme responsible for converting squalene to 2,3-oxydo squalene. As ergosterol is an essential component of the fungal cell membrane, inhibition of its synthesis results in increased cellular permeability causing leakage of cellular contents. Blockage of squalene monooxygenase also leads to a subsequent accumulation of squalene. When a high concentration of squalene is reached, it is thought to have an effect of directly kill fungal cells. Butenafine cream 1% is indicated in treatment of tinea pedis, tinea corporis and tinea cruris. In tinea pedis it is recommended twice daily for 7 days or once daily for 4 weeks. In tinea cruris and tinea corporis it is recommended once daily for two weeks.

SPORANOX is the brand name for itraconazole, an azole antifungal agent. Itraconazole is a 1:1:1:1 racemic mixture of four diastereomers (two enantiomeric pairs), each possessing three chiral centers. In vitro studies have demonstrated that itraconazole inhibits the cytochrome P450-dependent synthesis of ergosterol, which is a vital component of fungal cell membranes. As ergosterol is an essential component of the fungal cell membrane, inhibition of its synthesis results in increased cellular permeability causing leakage of cellular contents. Itraconazole may also inhibit endogenous respiration, interact with membrane phospholipids, inhibit the transformation of yeasts to mycelial forms, inhibit purine uptake, and impair triglyceride and/or phospholipid biosynthesis. SPORANOX capsules are indicated for the treatment of the following fungal infections in immunocompromised and non-immunocompromised patients: Blastomycosis, pulmonary and extrapulmonary; Histoplasmosis, including chronic cavitary pulmonary disease and disseminated, nonmeningeal histoplasmosis, and Aspergillosis, pulmonary and extrapulmonary, in patients who are intolerant of or who are refractory to amphotericin B therapy. SPORANOX is also indicated for the treatment of the following fungal infections in non-immunocompromised patients: Onychomycosis of the toenail, with or without fingernail involvement, due to dermatophytes (tinea unguium), and Onychomycosis of the fingernail due to dermatophytes (tinea unguium). Itraconazole is mainly metabolized through CYP3A4. Other drugs that either share this metabolic pathway or modify CYP3A4 activity may influence the pharmacokinetics of itraconazole. Similarly, itraconazole may modify the pharmacokinetics of other drugs that share this metabolic pathway. Itraconazole is a potent CYP3A4 inhibitor and a P-glycoprotein inhibitor. When using concomitant medication, it is recommended that the corresponding label be consulted for information on the route of metabolism and the possible need to adjust dosages.

Cefpodoxime is an orally administered, extended spectrum, semi-synthetic antibiotic of the cephalosporin class. Cefpodoxime is a bactericidal agent that acts by inhibition of bacterial cell wall synthesis. Cefpodoxime has activity in the presence of some beta-lactamases, both penicillinases and cephalosporinases, of Gram-negative and Gram-positive bacteria. Cefpodoxime is indicated for the treatment of patients with mild to moderate infections caused by susceptible strains of the designated microorganisms in the conditions: acute otitis media; pharyngitis and/or tonsillitis; community-acquired pneumonia; acute bacterial exacerbation of chronic bronchitis; gonorrhea; uncomplicated skin and skin structure infections; acute maxillary sinusitis and uncomplicated urinary tract infections (cystitis). Common adverse reactions include diarrhea, nausea, vaginal fungal infections, vulvovaginal infections, abdominal pain, headache. Concomitant administration of high doses of antacids (sodium bicarbonate and aluminum hydroxide) or H2 blockers reduces peak plasma levels by 24% to 42% and the extent of absorption by 27% to 32%, respectively. Oral anti-cholinergics (e.g., propantheline) delay peak plasma levels (47% increase in Tmax), but do not affect the extent of absorption (AUC). Probenecid: As with other beta-lactam antibiotics, renal excretion of cefpodoxime was inhibited by probenecid and resulted in an approximately 31% increase in AUC and 20% increase in peak cefpodoxime plasma levels.

Oxaprozin is a nonsteroidal anti-inflammatory drug (NSAID) with analgesic and antipyretic properties. Anti-inflammatory effects of Oxaprozin are believed to be due to inhibition of cylooxygenase in platelets which leads to the blockage of prostaglandin synthesis. Antipyretic effects may be due to action on the hypothalamus, resulting in an increased peripheral blood flow, vasodilation, and subsequent heat dissipation. Oxaprozin is a non-selective NSAID, with a cell assay system showing lower COX-2 selectivity implying higher COX-1 selectivity. Oxaprozin is used to treat rheumatoid arthritis, osteoarthritis, dysmenorrhea, and to alleviate moderate pain.

Rifabutin is an antibiotic that inhibits DNA-dependent RNA polymerase activity in susceptible cells. Specifically, it interacts with bacterial RNA polymerase but does not inhibit the mammalian enzyme. It is bactericidal and has a very broad spectrum of activity against most gram-positive and gram-negative organisms (including Pseudomonas aeruginosa) and specifically Mycobacterium tuberculosis. It is FDA approved for the prophylaxis of disseminated Mycobacterium avium complex (MAC) disease in patients with advanced HIV infection. Multiple dosing of rifabutin has been associated with induction of hepatic metabolic enzymes of the CYP3A subfamily. Rifabutin’s predominant metabolite (25-desacetyl rifabutin: LM565), may also contribute to this effect. Similarly, concomitant medications that competitively inhibit the CYP3A activity may increase plasma concentrations of rifabutin. Common adverse reactions include discoloration of skin, rash, diarrhea, disorder of taste, indigestion, loss of appetite, nausea, vomiting, increased liver aminotransferase level (mild), ocular discoloration, uveitis, abnormal color of body fluid.

Terbinafine (brand name Lamisil, Terbisil, Terboderm and others) is an antifungal medication used to treat ringworm and fungal nail infections. Terbinafine inhibits ergosterol synthesis by inhibiting squalene epoxidase, an enzyme that is part of the fungal cell membrane synthesis pathway. Because terbinafine prevents the conversion of squalene to lanosterol, ergosterol cannot be synthesized. This is thought to change cell membrane permeability, causing fungal cell lysis. Many side effects and adverse drug reactions have been reported with oral terbinafine hydrochloride possibly due to its extensive biodistribution and the often extended durations involved in antifungal treatment (longer than two months).

Desogestrel is a prodrug of etonogestrel (3-keto-desogestrel) which was approved as oral contraceptove medicine. Desogestrel acts selectively binding to progesterone receptor and enchancing its activity.