Ellagic acid is a dilactone of hexahydroxydiphenic acid, that found in numerous fruits and vegetables. Ellagic acid was first discovered by chemist Henri Braconnot in 1831. Ellagic acid is found in oaks species like the North American white oak (Quercus alba) and European red oak (Quercus robur). The highest levels of ellagic acid are found in walnuts, pecans, cranberries, raspberries, strawberries, and grapes, as well as distilled beverages. It is also found in peach, and other plant foods. Ellagic acid has antiproliferative and antioxidant properties in a number of in vitro and small-animal models. The antiproliferative properties of ellagic acid may be due to its ability to directly inhibit the DNA binding of certain carcinogens, including nitrosamines and polycyclic aromatic hydrocarbons. As with other polyphenol antioxidants, ellagic acid has a chemoprotective effect in cellular models by reducing oxidative stress. Ellagic acid is an investigational drug studied for treatment of Follicular Lymphoma (phase 2 trial), protection from brain injury of intrauterine growth restricted babies (phase 1 and 2 trial), improvement of cardiovascular function in adolescents who are obese (phase 2 trial), and topical treatment of solar lentigines. Ellagic acid has been marketed as a dietary supplement with a range of claimed benefits against cancer, heart disease, and other medical problems. Ellagic acid has been identified by the U.S. Food and Drug Administration as a "fake cancer 'cure' consumers should avoid".

Cinchophen, phenylcinchoninic acid, seems to have been discovered in 1887 by Doebner and Gieseke and to have been introduced into medicine under the trade name of atophan in 1908 by Nicolaier and Dohrn. Since that time it has been used extensively for gout as well as for other forms of arthritis and for the relief of pain of all types. Use of Cinchophen in humans ceased in the 1930s due to the discovery that it can cause serious liver damage.

Barbital, the one of the series of barbiturates, has hypnotic, sedative, and anticonvulsant properties and used under the trade name Veronal. It calmed manic patients and helped melancholic patients to sleep and was an effective inducer of sleep in insomniacs, but at the same time compound could induced dependence. It was substituted by the butyl analog, butobarbital, which was three times stronger and its period of action was much shorter due to its lipophilicity. Barbital is a ligand of GABA-receptor complex and in addition, it could have another target, a creatine kinase.

Noscapine (also known as Narcotine, Nectodon, Nospen, Anarcotine and (archaic) Opiane) is a benzylisoquinoline alkaloid from plants of the poppy family, without painkilling properties. This agent is primarily used for its antitussive (cough-suppressing) effects. Noscapine is often used as an antitussive medication. A 2012 Dutch guideline, however, does not recommend its use for coughing. Noscapine can increase the effects of centrally sedating substances such as alcohol and hypnotics. Noscapine should not be taken in conjunction with warfarin as the anticoagulant effects of warfarin may be increased. Noscapine, and its synthetic derivatives called noscapinoids, are known to interact with microtubules and inhibit cancer cell proliferation. Mechanisms for its antitussive action are unknown, although animal studies have suggested central nervous system as a site of action. Furthermore, noscapine causes apoptosis in many cell types and has potent antitumor activity against solid murine lymphoid tumors (even when the drug was administered orally) and against human breast and bladder tumors implanted in nude mice. Because noscapine is water-soluble and absorbed after oral administration, its chemotherapeutic potential in human cancer merits thorough evaluation. Antifibrotic effect of noscapine based on novel mechanism, which it shows through EP2 prostaglandin E2 receptor-mediated activation of protein kinase A.

Antipyrine is an analgesic and antipyretic that has been given by mouth and as ear drops. It is often used in testing the effects of other drugs or diseases on drug-metabolizing enzymes in the liver. It inhibits cyclooxygenases and shows little anti-inflammatory activity. Like many old and approved substances after almost 100 years of use, antipyrine has been associated with some serious side effects, namely agranulocytosis and shock reactions.

Lobeline is an alkaloid found in "Indian tobacco" (Lobelia inflata), "Devil's tobacco" (Lobelia tupa), "cardinal flower" (Lobelia cardinalis), "great lobelia" (Lobelia siphilitica), and Hippobroma longiflora. Additionally, it is also found in Lobelia Chinensis. In its pure form, it is a white amorphous powder which is freely soluble in water. Lobeline has been sold, in tablet form, for use as a smoking cessation aid, and may have application in the treatment of other drug addictions such as addiction to amphetamines, cocaine, or alcohol. Lobeline has multiple mechanisms of action, acting as a VMAT2 ligand, which stimulates dopamine release to a moderate extent when administered alone, but reduces the dopamine release caused by methamphetamine. It also inhibits the reuptake of dopamine and serotonin and acts as a mixed agonist-antagonist at nicotinic acetylcholine receptors to which it binds at the subunit interfaces of the extracellular domain. It is also an antagonist at μ-opioid receptors. It seems to be a P-glycoprotein inhibitor, according to at least one study. It has been hypothesized that P-glycoprotein inhibition reduces chemotherapeutic resistance in cancer, presumably affecting any substrates of P-gp.

Sodium 3,4-dimethylphenylglyoxylate is a topical analgesic, sunscreen ingredient, UV-B absorber, FDA approved.

Quinine ascorbate is a salt of antimalarial drug quinine and ascorbic acid (vitamin C). Ascorbate reduces the potency of quinolone-containing anti-malarial drugs. Quinine ascorbate was marketed as a component of over-the-counter smoking deterrent products but was not recognized as safe by the FDA regulation in 1993.

Dibenzothiophene (DBT) is the organosulfur compound consisting of two benzene rings fused to a central thiophene ring. It is a colourless solid that is chemically somewhat similar to anthracene. This tricyclicheterocycle, and especially its alkyl substituted derivatives, occur widely in heavier fractions of petroleum. A drug that softens, separates, and causes desquamation of the cornified epithelium or horny layer of skin. DBT was used to treat acne, seborrhea and related dermatoses.

Danthron, a natural product, was originally extracted from the roots and rhizome of Polygonaceae plant. Danthron is an anthraquinone. Danthron has been widely administrated as a laxative since the 1900s. In the United States, danthron has been forbidden to continual use as laxative because it is considered to be a carcinogen. In the UK, it is not marketed alone but in combination with poloxamer 188 as co-danthramer and with docusate as co-danthrusate; in the UK, its use is strictly restricted to the elderly and to the terminally ill of all ages because of concerns about carcinogenicity and hepatotoxicity. It has only a limited role in the treatment of constipation.