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Related to megestrol: megestrol acetate


a synthetic progestational agent administered orally as an antineoplastic agent for palliative treatment of recurrent, inoperable, or metastatic carcinoma of the breast or endometrium and for the treatment of anorexia, cachexia, and weight loss in patients with cancer or acquired immunodeficiency syndrome.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.


(me-jess-trole) ,


(trade name),

Megace ES

(trade name),

Megace OS

(trade name)


Therapeutic: antineoplastics
Pharmacologic: progestins
Pregnancy Category: D (tablets)
Pregnancy Category: X (suspension)


Palliative treatment of endometrial and breast carcinoma, either alone or with surgery or radiation (tablets only).Treatment of anorexia, weight loss, and cachexia associated with AIDS (oral suspension only).


Antineoplastic effect may result from inhibition of pituitary function.

Therapeutic effects

Regression of tumor.
Increased appetite and weight gain in patients with AIDS.


Absorption: Well absorbed from the GI tract.
Distribution: Unknown.
Protein Binding: ≥90%.
Metabolism and Excretion: Completely metabolized by the liver.
Half-life: 38 hr (range 13–104 hr).

Time/action profile (antineoplastic activity)

POwk–mos2 mounknown


Contraindicated in: Hypersensitivity;Undiagnosed vaginal bleeding;Severe liver disease;Suspension contains alcohol and should be avoided in patients with known intolerance; Obstetric / Lactation: Pregnancy or lactation.
Use Cautiously in: Diabetes;Mental depression;Renal disease;History of thrombophlebitis;Cardiovascular disease;Seizure disorders.

Adverse Reactions/Side Effects


  • thromboembolism (life-threatening)
  • edema


  • GI irritation


  • alopecia


  • asymptomatic adrenal suppression (chronic therapy) (most frequent)


  • vaginal bleeding


  • thrombophlebitis


  • carpal tunnel syndrome


Drug-Drug interaction

None significant.


Oral (Adults) Breast carcinoma—160 mg/day single dose or divided doses; endometrial/ovarian carcinoma—40–320 mg/day in divided doses; anorexia associated with AIDS—800 mg day; may ↓ to 400 mg/day after 1 mo (range 400–800 mg/day).

Availability (generic available)

Tablets: 20 mg, 40 mg
Oral suspensionlemon-lime flavor: 40 mg/mL, 125 mg/mL (Megace ES)

Nursing implications

Nursing assessment

  • Assess for swelling, pain, or tenderness in legs. Report these signs of deep vein thrombophlebitis.
  • Anorexia: Monitor weight, appetite, and nutritional intake in patients with AIDS.

Potential Nursing Diagnoses

Imbalanced nutrition: less than body requirements (Indications)


  • Because of high dose, suspension is most convenient form for patients with AIDS.
    • Do not confuse Megace 800 mg/20 mL with Megace ES 625 mg/5 mL.
  • Oral: May be administered with meals if GI irritation becomes a problem.

Patient/Family Teaching

  • Instruct patient to take medication exactly as directed; do not skip or double up on missed doses. Missed doses may be taken as long as it is not right before next dose. Gradually decrease dose prior to discontinuation.
  • Advise patient to report to health care professional any unusual vaginal bleeding or signs of deep vein thrombophlebitis.
  • Discuss with patient the possibility of hair loss. Explore methods of coping.
  • Advise patient that this medication may have teratogenic effects. Contraception should be used during therapy and for at least 4 mo after therapy is completed. Advise patient to notify health care professional immediately if pregnancy is planned or suspected or if breast feeding.

Evaluation/Desired Outcomes

  • Slowing or arresting the spread of endometrial or breast malignancy. Therapeutic effects usually occur within 2 mo of initiating therapy.
  • Increased appetite and weight gain in patients with AIDS.
Drug Guide, © 2015 Farlex and Partners


A PROGESTOGEN drug used to assist in the treatment of breast or endometrial cancer. A brand name is Megace.
Collins Dictionary of Medicine © Robert M. Youngson 2004, 2005
References in periodicals archive ?
Fenstermaker, "Intracranial meningiomas in patients with uterine sarcoma treated with long-term megestrol acetate therapy," World Neurosurgery, vol.
Bruera, "Association between megestrol acetate treatment and symptomatic adrenal insufficiency with hypogonadism in male patients with cancer," Cancer, vol.
The company said the Megestrol Acetate Oral Suspension is the generic version of MegaceES by Strativa Pharmaceuticals, a division of Par Pharmaceutical Inc.
We found inpatients aged 80 years or older have more PIM use and encounter more potential inappropriate prescription of benzodiazepines, drugs with strong anticholinergic properties, megestrol, antipsychotics, theophylline, and aspirin than patients aged 65-79 years.
Treatment with nandrolone decanoate and megestrol acetate in HIV-infected men.
AS PART OF ITS NEW WOMEN'S WELLNESS INITIATIVE, representatives of Schnucks Pharmacies have made four different oral breast cancer medications (Letrozole, Megestrol, Anastrozole and Tamoxifen) available for only $9 with a prescription.
Eleven of those 25 were black, and 10 were taking megestrol acetate (Megace), a synthetic progesterone then prescribed to stimulate appetite in people with HIV but now rarely used by HIV-positive people.
(52) However, co-administration of megestrol acetate, a potent progesterone receptor agonist, reversed the abortifacient effect.
And megestrol (a progestin drug) treatment has produced some efficacy in advanced HCC in some clinical studies [18, 19].
Shi, "Clinical study on treatment of female idiopathic precocious puberty with combined therapy of Chinese medicine and megestrol acetate," Chinese Journal of Integrated Traditional and Western Medicine, vol.