Triamterene, a relatively weak, potassium-sparing diuretic and antihypertensive, is used in the management of hypokalemia. Triamterene inhibits the epithelial sodium channels on principal cells in the late distal convoluted tubule and collecting tubule, which are responsible for 1-2% of total sodium reabsorption. As sodium reabsorption is inhibited, this increases the osmolarity in the nephron lumen and decreases the osmolarity of the interstitium. Since sodium concentration is the main driving force for water reabsorption, triamterene can achieve a modest amount of diuresis by decreasing the osmotic gradient necessary for water reabsorption from lumen to interstitium. Triamterene also has a potassium-sparing effect. Normally, the process of potassium excretion is driven by the electrochemical gradient produced by sodium reabsorption. As sodium is reabsorbed, it leaves a negative potential in the lumen, while producing a positive potential in the principal cell. This potential promotes potassium excretion through apical potassium channels. By inhibiting sodium reabsorption, triamterene also inhibits potassium excretion.Triamterene is used for the treatment of edema associated with congestive heart failure, cirrhosis of the liver, and the nephrotic syndrome; also in steroid-induced edema, idiopathic edema, and edema due to secondary hyperaldosteronism. Triamterene is maeketed under the trade name Dyrenium.

Penicillin V is a penicillin beta-lactam antibiotic used in the treatment of bacterial infections caused by susceptible, usually gram-positive, organisms. The name "penicillin" can either refer to several variants of penicillin available, or to the group of antibiotics derived from the penicillins. Penicillin V has in vitro activity against gram-positive and gram-negative aerobic and anaerobic bacteria. The bactericidal activity of Penicillin V results from the inhibition of cell wall synthesis and is mediated through Penicillin V binding to penicillin binding proteins (PBPs). Penicillin V is stable against hydrolysis by a variety of beta-lactamases, including penicillinases, and cephalosporinases and extended spectrum beta-lactamases. By binding to specific penicillin-binding proteins (PBPs) located inside the bacterial cell wall, Penicillin V inhibits the third and last stage of bacterial cell wall synthesis. Cell lysis is then mediated by bacterial cell wall autolytic enzymes such as autolysins; it is possible that Penicillin V interferes with an autolysin inhibitor. Used for the treatment of mild to moderately severe infections (e.g. dental infection, infections in the heart, middle ear infections, rheumatic fever, scarlet fever, skin infections, upper and lower respiratory tract infections) due to microorganisms.

Methoxsalen — also called xanthotoxin, marketed under the trade names Oxsoralen, Deltasoralen, Meladinine — is a drug used to treat psoriasis, eczema, vitiligo, and some cutaneous lymphomas in conjunction with exposing the skin to UVA light from lamps or sunlight. Methoxsalen modifies the way skin cells receive the UVA radiation, allegedly clearing up the disease. The dosage comes in 10 mg tablets, which are taken in the amount of 30 mg 75 minutes before a PUVA (psoralen + UVA) light treatment. Chemically, methoxsalen belongs to a class of organic natural molecules known as furanocoumarins. They consist of coumarin annulated with furan. It can also be injected and used topically. The exact mechanism of action of methoxsalen with the epidermal melanocytes and keratinocytes is not known. The best known biochemical reaction of methoxsalen is with DNA. Methoxsalen, upon photoactivation, conjugates and forms covalent bonds with DNA which leads to the formation of both monofunctional (addition to a single strand of DNA) and bifunctional adducts (crosslinking of psoralen to both strands of DNA) Reactions with proteins have also been described. Methoxsalen acts as a photosensitizer. Administration of the drug and subsequent exposure to UVA can lead to cell injury. Orally administered methoxsalen reaches the skin via the blood and UVA penetrates well into the skin. If sufficient cell injury occurs in the skin, an inflammatory reaction occurs. The most obvious manifestation of this reaction is delayed erythema, which may not begin for several hours and peaks at 48–72 hours. The inflammation is followed, over several days to weeks, by repair which is manifested by increased melanization of the epidermis and thickening of the stratum corneum. The mechanisms of therapy are not known. In the treatment of vitiligo, it has been suggested that melanocytes in the hair follicle are stimulated to move up the follicle and to repopulate the epidermis. In the treatment of psoriasis, the mechanism is most often assumed to be DNA photodamage and resulting decrease in cell proliferation but other vascular, leukocyte, or cell regulatory mechanisms may also be playing some role. Psoriasis is a hyperproliferative disorder and other agents known to be therapeutic for psoriasis are known to inhibit DNA synthesis. The most commonly reported side effect of methoxsalen alone is nausea, which occurs with approximately 10% of all patients. This effect may be minimized or avoided by instructing the patient to take methoxsalen with milk or food, or to divide the dose into two portions, taken approximately one-half hour apart. Other effects include nervousness, insomnia, and psychological depression.

Penicillin G, also known as benzylpenicillin, is a penicillin derivative commonly used in the form of its sodium or potassium salts in the treatment of a variety of infections. It is effective against most gram-positive bacteria and against gram-negative cocci. It is administered intravenously or intramuscularly due to poor oral absorption. Penicillin G may also be used in some cases as prophylaxis against susceptible organisms. Microbiology Penicillin G is bactericidal against penicillin-susceptible microorganisms during the stage of active multiplication. It acts by inhibiting biosynthesis of cell-wall mucopeptide. It is not active against the penicillinase-producing bacteria, which include many strains of staphylococci. Penicillin G is highly active in vitro against staphylococci (except penicillinase-producing strains), streptococci (groups A, B, C, G, H, L and M), pneumococci and Neisseria meningitidis. Other organisms susceptible in vitro to penicillin G are Neisseria gonorrhoeae, Corynebacterium diphtheriae, Bacillus anthracis, clostridia, Actinomyces species, Spirillum minus, Streptobacillus monillformis, Listeria monocytogenes, and leptospira; Treponema pallidum is extremely susceptible. Adverse effects can include hypersensitivity reactions including urticaria, fever, joint pains, rashes, angioedema, anaphylaxis, serum sickness-like reaction.

Alcohols exhibit rapid broad-spectrum antimicrobial activity against vegetative bacteria (including mycobacteria), viruses, and fungi but are not sporicidal. They are, however, known to inhibit sporulation and spore germination, but this effect is reversible. Because of the lack of sporicidal activity, alcohols are not recommended for sterilization but are widely used for both hard-surface disinfection and skin antisepsis. Lower concentrations may also be used as preservatives and to potentiate the activity of other biocides. Many alcohol products include low levels of other biocides (in particular chlorhexidine), which remain on the skin following evaporation of the alcohol, or excipients (including emollients), which decrease the evaporation time of the alcohol and can significantly increase product efficacy. Ethanol in combination with: chlorhexidine gluconate 1% was approved to use in surgical hand antiseptic. It significantly reduces the number of microorganisms on the hands and forearms prior to surgery or patient care. Ethanol is also used as a co-solvent to dissolve many insoluble drugs and to serve as a mild sedative in some medicinal formulations. Ethanol is metabolized by the hepatic enzyme alcohol dehydrogenase. Ethanol affects the brain’s neurons in several ways. It alters their membranes as well as their ion channels, enzymes, and receptors. Alcohol also binds directly to the receptors for acetylcholine, serotonin, GABA, and the NMDA receptors for glutamate. The sedative effects of ethanol are mediated through binding to GABA receptors and glycine receptors (alpha 1 and alpha 2 subunits). It also inhibits NMDA receptor functioning. In its role as an anti-infective, ethanol acts as an osmolyte or dehydrating agent that disrupts the osmotic balance across cell membranes.

Oxarbazole was developed as an antiasthmatic agent that inhibited the only bronchoconstriction induced by immune complexes. This drug has never been marketed.

Adicillin (Penicillin N) is a penicillin derivative produced by Cephalosporium acremonium. Adicillin is dextrorotatory. Inactivated by penicillinase as is penicillin G, but differs from the common penicillin by its antibacterial activity and hydrophilic character. Active against Sarcina lutea, Proteus vulgaris, Salmonella typhimurium, Diplococcus pneumoniae. Shows practically no activity against B. subtilis and Staph. aureus. The toxicity is somewhat less than that of penicillin G, although penicillin N is excreted more slowly.