Cholic acid is a primary bile acid synthesized from cholesterol in the liver. Endogenous bile acids including cholic acid enhance bile flow and provide the physiologic feedback inhibition of bile acid synthesis. The mechanism of action of cholic acid has not been fully established; however, it is known that cholic acid and its conjugates are endogenous ligands of the nuclear receptor, farnesoid X receptor (FXR). FXR regulates enzymes and transporters that are involved in bile acid synthesis and in the enterohepatic circulation to maintain bile acid homeostasis under normal physiologic conditions. U.S. Food and Drug Administration approved Cholbam (cholic acid) capsules, the first FDA approved treatment for pediatric and adult patients with bile acid synthesis disorders due to single enzyme defects, and for patients with peroxisomal disorders (including Zellweger spectrum disorders).

Carglumic acid is a Carbamoyl Phosphate Synthetase 1 (CPS 1) allosteric modulator. CPS1 is found in the mitochondria and is the first enzyme of the urea cycle, which converts ammonia into urea. Carglumic acid acts as a replacement for NAG in NAGS deficiency patients by activating CPS1 but it does not help to regulate the urea cycle. Carglumic acid under the trade name Carbaglu indicated as adjunctive therapy for the treatment of acute hyperammonemia due to the deficiency of the hepatic enzyme N-acetylglutamate synthase (NAGS). In addition, as maintenance therapy for the treatment of chronic hyperammonemia due to the deficiency of the hepatic enzyme N-acetylglutamate synthase (NAGS). This rare genetic disorder results in elevated blood levels of ammonia, which can eventually cross the blood–brain barrier and cause neurologic problems, cerebral edema, coma, and death.

Ethacrynic acid is a monosulfonamyl loop or high ceiling diuretic. Ethacrynic acid acts on the ascending limb of the loop of Henle and on the proximal and distal tubules. Urinary output is usually dose dependent and related to the magnitude of fluid accumulation. Water and electrolyte excretion may be increased several times over that observed with thiazide diuretics, since ethacrynic acid inhibits reabsorption of a much greater proportion of filtered sodium than most other diuretic agents. Therefore, ethacrynic acid is effective in many patients who have significant degrees of renal insufficiency. Ethacrynic acid has little or no effect on glomerular filtration or on renal blood flow, except following pronounced reductions in plasma volume when associated with rapid diuresis. Ethacrynic acid inhibits symport of sodium, potassium, and chloride primarily in the ascending limb of Henle, but also in the proximal and distal tubules. This pharmacological action results in excretion of these ions, increased urinary output, and reduction in extracellular fluid. Diuretics also lower blood pressure initially by reducing plasma and extracellular fluid volume; cardiac output also decreases, explaining its antihypertensive action. Eventually, cardiac output returns to normal with an accompanying decrease in peripheral resistance. Its mode of action does not involve carbonic anhydrase inhibition. Ethacrynic acid is indicated for the treatment of high blood pressure and edema caused by diseases like congestive heart failure, liver failure, and kidney failure.

Mefenamic acid is a non-steroidal anti-inflammatory agent with analgesic, anti-inflammatory, and antipyretic properties. It is used for the treatment of mild to moderate pain, including menstrual pain, inflammation, and fever. Clinical use of mefenamic acid has generally declined in an era where other NSAID use has flourished. While having modes of action and general toxicities similar to other NSAIDs, mefenamic acid, as a member of the fenamates, nevertheless possesses some unique in vitro effects that have the potential to distinguish this agent from others. Use of this drug remains relevant for pain syndromes and some gynecological disorders, albeit with considerable competition from other NSAIDs. New basic science has considerably improved the understanding of the biochemistry of mefenamic acid. As well as maintaining its use in traditional settings, there is a tremendous potential for expanding the application of mefenamic acid to niche roles. Mefenamic acid binds the prostaglandin synthetase receptors COX-1 and COX-2, inhibiting the action of prostaglandin synthetase. Mefenamic acid concentrations reached during therapy have produced in vivo effects. Prostaglandins sensitize afferent nerves and potentiate the action of bradykinin in inducing pain in animal models. Prostaglandins are mediators of inflammation. Because mefenamic acid is an inhibitor of prostaglandin synthesis, its mode of action may be due to a decrease of prostaglandins in peripheral tissues.

Folic Acid is a B complex vitamin containing a pteridine moiety linked by a methylene bridge to para-aminobenzoic acid, which is joined by a peptide linkage to glutamic acid. Conjugates of Folic Acid are present in a wide variety of foods, particularly liver, kidneys, yeast and leafy green vegetables. Commercially available Folic Acid is prepared synthetically. Folic Acid occurs as a yellow or yellowish-orange crystalline powder and is very slightly soluble in water and insoluble in alcohol. Aqueous solutions of Folic Acid are heat sensitive and rapidly decompose in the presence of light and/or riboflavin; solutions should be stored in a cool place protected from light. Folic Acid is effective in the treatment of megaloblastic anemias due to a deficiency of Folic Acid (as may be seen in tropical or nontropical sprue) and in anemia of nutritional origin, pregnancy, infancy, or childhood. Folic Acid is relatively nontoxic in man. Rare instances of allergic responses to Folic Acid preparations have been reported and have included erythema, skin rash, itching, general malaise, and respiratory difficulty due to bronchospasm. Endocyte is developing an intravenous (IV) formulation of folic acid, called Neocepri®, which is intended for the diagnosis of positive folate receptor-positive status in patients with ovarian cancer when administered prior to the radioactive medicine, technetium Tc99m Etarfolatide. The benefits of Neocepri® are its ability to reduce the background activity observed on single photon emission computed tomography (SPECT) imaging in most normal, nontarget tissues (e.g. intestines, liver, kidney, spleen), thereby improving the image quality of the scans. The product had been granted orphan drug designation in the EU. Endocyte had filed a conditional marketing authorization application (CMA) with the European Medicines Agency (EMA) for Neocepri®.

Methyl salicylate (or methyl 2-hydroxybenzoate), also known as wintergreen oil, is a natural product and is present in white wine, tea, porcini mushroom Boletus edulis, Bourbon vanilla, clary sage, red sage and fruits including cherry, apple, raspberry, papaya and plum. Methyl salicylate is topically used in combination with methanol and under brand name SALONPAS to temporarily relieves mild to moderate aches and pains of muscles and joints associated with: strains, sprains, simple backache, arthritis, bruises. The precise mechanism of action of methyl salicylate is not known, but there is suggested, that it cause dilation of the capillaries thereby increasing blood flow to the area.

3-Indolepropionic acid (IN-OX1; Indole-3-propionic acid; OX-1; Oxigon; SHP 22; SHP-622; VP-20629), an endogenous substance produced by bacteria in the intestine, is a deamination product of Tryptophan (T947200) that protects the hippocampus (studied in gerbils) from ischemic damage and oxidative stress. It’s ability to protect the neurons in this way is attributed to its potent antioxidative effects. 3-Indolepropionic acid is also hypothesized to have protective effects on the thyroid gland. 3-Indolepropionic acid is being studied for therapeutic use in Alzheimer's disease. 3-Indolepropionic acid (IPA) completely protected primary neurons and neuroblastoma cells against oxidative damage and death caused by exposure to Abeta, by inhibition of superoxide dismutase, or by treatment with hydrogen peroxide. In kinetic competition experiments using free radical-trapping agents, the capacity of IPA to scavenge hydroxyl radicals exceeded that of melatonin, an indoleamine considered to be the most potent naturally occurring scavenger of free radicals. In contrast with other antioxidants, IPA was not converted to reactive intermediates with pro-oxidant activity. In 2011, Intellect redirected the focus of the OX1 program from Alzheimer's disease to FA (Friedreich's Ataxia). Research suggests that the symptoms associated with FA are the result of oxidative stress caused by the abnormal accumulation of iron. OX1's ability to neutralize ROS could be an effective agent to reduce oxidative stress in FA, thereby eliminating the symptoms of FA and increasing both quality of life and longevity in affected individuals.

Delmitide is the decapeptide with antiinflammatory activity. It is the first low molecular weight compound inhibiting TNF production at a translational level. Also, delmitide inhibits production of IFN-gamma, IL-12 and IL-2. It targets TRAF6/IRAK4/MyD88 complex and inhibits phosphorylation of SAPKs (p38 and JNK). Delmitide inhibits AP1 and NFkB activation. Delmitide was developed for the potential treatment of Crohn's disease and ulcerative colitis; phase II trials for both these indications commenced in October 2001. Phase I trial in chemotherapy-induced diarrhea and the gastrointestinal complications of HIV were also initiated. However, no recent development has been reported.