Metacresol (m-cresol or 3-methylphenol) is colorless, yellowish liquid. It is used as a bactericide for control of crown gall and olive knot on certain fruit and nut trees and ornamentals and the genetic/physiological disorder burr knot on apples. Currently, one product is registered which contains both m-cresol and xylenol. Used as disinfectant/bacteriocide/germicide for animal pathogenic bacteria (G- and G+ vegetative) in households, sickrooms, hospitals, veterinary clinics, and veterinary hospitals; on surgical instruments, diagnostic instruments/equipment and on hospital critical rubber/plastic items. Used as an insecticide and miticide on dogs for treatment of lice and fleas. It is also used for making synthetic resins; in photographic developers, explosives. Additionally, m-cresol is chemical intermediate for thymol used in cough/cold medicinals, synthetic pyrethroid insecticides, 3-methyl-6-t-butylphenol, trinitro-m-cresol for explosives, and phenolic resins; disinfectant ingredient; ore flotation agent; solvent. m-Cresol, either pure or mixed with p-cresol, is important in the production of contact herbicides. m-Cresol is also a precursor to the pyrethroid insecticides. Furthermore, many flavor and fragrance compounds, such as (-)-methanol and musk ambrette, are derived from m-cresol. Several important antioxidants including synthetic vitamin E are produced from m-cresol. m-cresol is used as a topical dental antiseptic. m-cresol is an effective antimicrobial preservative and is used at low levels (0.3%) in multi-dose peptide and protein formulations. m-cresol has been shown to cause protein aggregation.

Allopurinol is a xanthine oxidase inhibitor used to decrease high blood uric acid levels. Allopurinol is specifically used to prevent gout, prevent specific types of kidney stones, and for the high uric acid levels that can occur with chemotherapy. Allopurinol acts on purine catabolism, without disrupting the biosynthesis of purines. It reduces the production of uric acid by inhibiting the biochemical reactions immediately preceding its formation. Allopurinol is a structural analog of the natural purine base, hypoxanthine. It is an inhibitor of xanthine oxidase, the enzyme responsible for the conversion of hypoxanthine to xanthine and of xanthine to uric acid, the end product of purine metabolism in man. Allopurinol is metabolized to the corresponding xanthine analog, oxypurinol (Allopurinol), which also is an inhibitor of xanthine oxidase. Allopurinol is taken by mouth or injected into a vein. Common side effects, when used by mouth, include itchiness and rash. Common side effects when used by injection include vomiting and kidney problems.