Megestrol acetate

384.51

384.51

209-864-5

TJ2M0FR8ES

71423

DTXSID9040683

C1156

29372390

60.4

3.2

Crystalline Solid

1.2±0.1 g/cm3

214 °C

431.17°C (rough estimate)

218.5±30.2 °C

1.551

2 µg/mL (at 37 °C for the acetate salt)

Refrigerator

LD50 intravenous in mouse: 56mg/kg

D24 +5° (chloroform)

180.1 Ų [M+H-H2O]+ [CCS Type: TW, Method: calibrated with polyalanine and drug standards]

NONH for all modes of transport

3

40-48

22-24/25

TU4075000

Xn

P281

H351-H373

|Danger|H302 (14.63%): Harmful if swallowed [Warning Acute toxicity, oral]|P201, P202, P260, P261, P263, P264, P270, P271, P280, P281, P301+P312, P302+P352, P304+P312, P304+P340, P308+P313, P312, P314, P322, P330, P363, P405, and P501|Aggregated GHS information provided by 123 companies from 15 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.

No serious unexpected side effects have resulted from studies involving megestrol acetate oral suspension administered in dosages as high as 1200 mg/day. Treatment with megestrol acetate, an orexigenic agent, has also resulted in iatrogenic adrenal suppression. The mechanism is presumably related to the glucocorticoid properties of megestrol acetate [PMID: 12872362].

For the treatment of anorexia, cachexia, or an unexplained, significant weight loss in patients with a diagnosis of acquired immunodeficiency syndrome (AIDS). Also used for the palliative management of recurrent, inoperable, or metastatic breast cancer, endometrial cancer, and prostate cancer in Canada and some other countries.|FDA Label|Drug: Megestrolacetate

Megestrol is a synthetic progestin and has the same physiologic effects as natural progesterone. These effects include induction of secretory changes in the endometrium, increase in basal body temperature, pituitary inhibition, and production of withdrawal bleeding in the presence of estrogen. Mestrogel has slight glucocorticoid activity and very slight mineralocorticoid activity. This drug has no estrogenic, androgenic, or anabolic activity. The precise mechanism of megestrol’s antianorexic and anticachetic effects is unknown. Initially developed as a contraceptive, it was first evaluated in breast cancer treatment in 1967.

Antineoplastic agents that are used to treat hormone-sensitive tumors. Hormone-sensitive tumors may be hormone-dependent, hormone-responsive, or both. A hormone-dependent tumor regresses on removal of the hormonal stimulus, by surgery or pharmacological block. Hormone-responsive tumors may regress when pharmacologic amounts of hormones are administered regardless of whether previous signs of hormone sensitivity were observed. The major hormone-responsive cancers include carcinomas of the breast, prostate, and endometrium; lymphomas; and certain leukemias. (From AMA Drug Evaluations Annual 1994, p2079) (See all compounds classified as Antineoplastic Agents, Hormonal.)|Agents that are used to stimulate appetite. These drugs are frequently used to treat anorexia associated with cancer and AIDS. (See all compounds classified as Appetite Stimulants.)

Variable, but well absorbed orally.|The major route of drug elimination in humans is urine. Respiratory excretion as labeled carbon dioxide and fat storage may have accounted for at least part of the radioactivity not found in urine and feces.

Primarily hepatic. Megestrol metabolites which were identified in urine constituted 5% to 8% of the dose administered. Respiratory excretion as labeled carbon dioxide and fat storage may have accounted for at least part of the radioactivity not found in urine and feces. No active metabolites have been identified.

34 hours

The precise mechanism by which megestrol acetate produces effects in anorexia and cachexia is unknown at the present time, but its progestin antitumour activity may involve suppression of luteinizing hormone by inhibition of pituitary function. Studies also suggest that the megestrol's weight gain effect is related to its appetite-stimulant or metabolic effects rather than its glucocorticoid-like effects or the production of edema. It has also been suggested that megestrol may alter metabolic pathyways via interferences with the production or action of mediators such as cachectin, a hormone that inhibits adipocyte lipogenic enzymes.

Acetate, Megestrol

Human drugs -> Rare disease (orphan)|Human Drugs -> FDA Approved Drug Products with Therapeutic Equivalence Evaluations (Orange Book) -> Active Ingredients|Animal Drugs -> FDA Approved Animal Drug Products (Green Book) -> Active Ingredients|Lipids -> Sterol Lipids [ST] -> Steroids [ST02] -> C21 steroids (gluco/mineralocorticoids, progestogins) and derivatives [ST0203]|Pharmaceuticals -> Animal Drugs -> Approved in Taiwan