Megestrol acetate

Megestrol acetate
Clinical data
Trade namesMegace, others
Other namesMGA; BDH-1298; NSC-71423; SC-10363; 17α-Acetoxy-6-dehydro-6-methylprogesterone; 17α-Acetoxy-6-methylpregna-4,6-diene-3,20-dione
License data
Routes of
administration		By mouth
Drug classProgestogen; Progestin; Progestogen ester; Antigonadotropin; Steroidal antiandrogen
ATC code
Legal status
Legal status
Pharmacokinetic data
Bioavailability100%[2]
Protein binding82% to albumin,[3] no affinity for SHBGTooltip sex hormone-binding globulin or CBGTooltip corticosteroid-binding globulin[2][4]
MetabolismLiver (hydroxylation, reduction, conjugation)[6]
Elimination half-lifeMean: 34 hours[5]
Range: 13–105 hours[5]
ExcretionUrine: 57–78%[6]
Feces: 8–30%[6]
Identifiers
  • [(8R,9S,10R,13S,14S,17R)-17-acetyl-6,10,13-trimethyl-3-oxo-2,8,9,11,12,14,15,16-octahydro-1H-cyclopenta[a]phenanthren-17-yl] acetate
CAS Number
PubChem CID
DrugBank
ChemSpider
UNII
KEGG
ChEBI
CompTox Dashboard (EPA)
ECHA InfoCard100.008.969 Edit this at Wikidata
Chemical and physical data
FormulaC24H32O4
Molar mass384.516 g·mol−1
3D model (JSmol)
  • CC1=C[C@@H]2[C@H](CC[C@]3([C@H]2CC[C@@]3(C(=O)C)OC(=O)C)C)[C@@]4(C1=CC(=O)CC4)C
  • InChI=1S/C24H32O4/c1-14-12-18-19(22(4)9-6-17(27)13-21(14)22)7-10-23(5)20(18)8-11-24(23,15(2)25)28-16(3)26/h12-13,18-20H,6-11H2,1-5H3/t18-,19+,20+,22-,23+,24+/m1/s1
  • Key:RQZAXGRLVPAYTJ-GQFGMJRRSA-N

Megestrol acetate (MGA), sold under the brand name Megace among others, is a progestin medication which is used mainly as an appetite stimulant to treat wasting syndromes such as cachexia.[2][5][7][1] It is also used to treat breast cancer and endometrial cancer, and has been used in birth control.[5][7][8][9] Megestrol acetate is generally formulated alone, although it has been combined with estrogens in birth control formulations.[10] It is usually taken by mouth.[2]

Side effects of megestrol acetate include increased appetite, weight gain, vaginal bleeding, nausea, edema, low sex hormone levels, sexual dysfunction, osteoporosis, cardiovascular complications, glucocorticoid effects, and others.[7] Megestrol acetate is a progestin, or a synthetic progestogen, and hence is an agonist of the progesterone receptor, the biological target of progestogens like progesterone.[2] It has weak partial androgenic activity, weak glucocorticoid activity, and no other important hormonal activity.[2] Due to its progestogenic activity, megestrol acetate has antigonadotropic effects.[7] The mechanism of action of the appetite stimulant effects of megestrol acetate is unknown.[11][12][13]

Megestrol acetate was discovered in 1959 and was introduced for medical use, specifically in birth control pills, in 1963.[8][9][14] It may be considered a "first-generation" progestin.[15] The medication was withdrawn in some countries in 1970 due to concerns about mammary toxicity observed in dogs, but this turned out not to apply to humans.[16][17][18][19][20] Megestrol acetate was approved for the treatment of endometrial cancer in 1971 and wasting syndromes in 1993.[7][21] It is marketed widely throughout the world.[22][23] It is available as a generic medication.[24]

  1. ^ a b "Megace ES- megesterol acetate suspension". DailyMed. 18 March 2014. Retrieved 30 December 2023.
  2. ^ a b c d e f Kuhl H (August 2005). "Pharmacology of estrogens and progestogens: influence of different routes of administration" (PDF). Climacteric. 8 (Suppl 1): 3–63. doi:10.1080/13697130500148875. PMID 16112947. S2CID 24616324.
  3. ^ Cite error: The named reference ChuLi1986b was invoked but never defined (see the help page).
  4. ^ Schindler AE, Campagnoli C, Druckmann R, Huber J, Pasqualini JR, Schweppe KW, et al. (December 2003). "Classification and pharmacology of progestins". Maturitas. 46 (Suppl 1): S7–S16. doi:10.1016/j.maturitas.2003.09.014. PMID 14670641.
  5. ^ a b c d Barakat RR, Markman M, Randall M (2009). Principles and Practice of Gynecologic Oncology. Lippincott Williams & Wilkins. pp. 447–. ISBN 978-0-7817-7845-9.
  6. ^ a b c Canetta R, Florentine S, Hunter H, Lenaz L (September 1983). "Megestrol acetate". Cancer Treatment Reviews. 10 (3): 141–157. doi:10.1016/0305-7372(83)90029-4. PMID 6352021.
  7. ^ a b c d e Schacter L, Rozencweig M, Canetta R, Kelley S, Nicaise C, Smaldone L (March 1989). "Megestrol acetate: clinical experience". Cancer Treatment Reviews. 16 (1): 49–63. doi:10.1016/0305-7372(89)90004-2. PMID 2471590.
  8. ^ a b Cite error: The named reference Marks2010 was invoked but never defined (see the help page).
  9. ^ a b Cite error: The named reference pmid13934321 was invoked but never defined (see the help page).
  10. ^ Cite error: The named reference MortonHall1999 was invoked but never defined (see the help page).
  11. ^ Cite error: The named reference BergerShuster2006 was invoked but never defined (see the help page).
  12. ^ Cite error: The named reference Jörres2010 was invoked but never defined (see the help page).
  13. ^ Cite error: The named reference Ettinger2008 was invoked but never defined (see the help page).
  14. ^ Cite error: The named reference Springer2012 was invoked but never defined (see the help page).
  15. ^ Gordon JD (2007). Obstetrics, Gynecology & Infertility: Handbook for Clinicians. Scrub Hill Press, Inc. pp. 228–. ISBN 978-0-9645467-7-6.
  16. ^ Cite error: The named reference UnitedNations1983 was invoked but never defined (see the help page).
  17. ^ Cite error: The named reference pmid4126857 was invoked but never defined (see the help page).
  18. ^ Cite error: The named reference FDAConsumer1976 was invoked but never defined (see the help page).
  19. ^ Cite error: The named reference Welfare1976 was invoked but never defined (see the help page).
  20. ^ Cite error: The named reference RunnebaumRabe2012b was invoked but never defined (see the help page).
  21. ^ Cite error: The named reference EiblEdderkaoui2015 was invoked but never defined (see the help page).
  22. ^ Cite error: The named reference IndexNominum2000 was invoked but never defined (see the help page).
  23. ^ Cite error: The named reference Drugs.com was invoked but never defined (see the help page).
  24. ^ "Generic Megace Availability".