While the 19-nortestosterone progestins are consistently grouped into generations, the pregnane progestins that are or have been used in birth control pills are typically omitted from such classifications or are grouped simply as "miscellaneous" or "pregnanes". In any case, based on its date of introduction in such formulations of 1963, MGA could be considered a "first-generation" progestin. Research
MGA has been studied in men in combination with testosterone as a male hormonal contraceptive to suppress spermatogenesis. Veterinary use
MGA has been used in veterinary medicine under the brand name Ovaban in the treatment of medical conditions in cats and dogs. Due to its ability to suppress testosterone levels, MGA can control sexually dimorphic traits in males. As a result, MGA has been used to reduce dominance, inter-male aggression, mounting, urine spraying, and roaming in male dogs and cats. See also
Estradiol/megestrol acetate
Ethinylestradiol/megestrol acetate

References


== Further reading ==
Against rheumatoid arthritis, it operates by inhibiting lymphocyte proliferation, phospholipase A2, antigen presentation in dendritic cells, release of enzymes from lysosomes, release of reactive oxygen species from macrophages, and production of IL-1. History
In Peru, the indigenous people extracted the bark of the Cinchona tree (Cinchona officinalis) and used the extract to fight chills and fever in the seventeenth century. In 1633 this herbal medicine was introduced in Europe, where it was given the same use and also began to be used against malaria. The quinoline antimalarial drug quinine was isolated from the extract in 1820.: 130–131 After World War I, the German government sought alternatives to quinine. Chloroquine, a synthetic analogue with the same mechanism of action was discovered in 1934, by Hans Andersag and coworkers at the Bayer laboratories, who named it Resochin. It was ignored for a decade, because it was considered too toxic for human use. Instead, in World War II, the German Africa Corps used the chloroquine analogue 3-methyl-chloroquine, known as Sontochin. After Allied forces arrived in Tunis, Sontochin fell into the hands of Americans, who sent the material back to the United States for analysis, leading to renewed interest in chloroquine. United States government-sponsored clinical trials for antimalarial drug development showed unequivocally that chloroquine has a significant therapeutic value as an antimalarial drug. : 61–66  It was introduced into clinical practice in 1947 for the prophylactic treatment of malaria. Chemical synthesis
The first synthesis of chloroquine was disclosed in a patent filed by IG Farben in 1937.