me-JESS-trole

Therapeutic Classification: antineoplastics, hormones

Pharmacologic Classification: progestins

• 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.

• 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/Excretion: Completely metabolized by the liver.

Half-life: 38 hr (range 13–104 hr).

(antineoplastic activity)

Contraindicated in:

• Hypersensitivity
• Undiagnosed vaginal bleeding
• Severe hepatic impairment
• Suspension contains alcohol and should be avoided in patients with known intolerance
• OB: Pregnancy
• Lactation: Lactation.

Use Cautiously in:

• Diabetes
• Mental depression
• Renal impairment
• History of thrombophlebitis
• Cardiovascular disease
• Seizures
• Women of reproductive potential
• Pedi: Safety and effectiveness not established in children
• Geri: Appears on Beers list. ↑ risk of thrombotic events and possibly death in older adults. Avoid use in older adults.

CV: edema, THROMBOEMBOLISM.

Derm: alopecia.

Endo: asymptomatic adrenal suppression (chronic therapy).

GI: GI irritation.

GU: vaginal bleeding.

MS: carpal tunnel syndrome.

Drug-Drug:

• May ↑ INR and risk of bleeding when used with warfarin.

• PO (Adults): Breast carcinoma: 160 mg/day as a single dose or divided doses; Endometrial/ovarian carcinoma: 40–320 mg/day in divided doses; Anorexia associated with AIDS: 40 mg/mL suspension: 800 mg once daily; may ↓ to 400 mg/day after 1 mo (range 400–800 mg/day); 125 mg/mL suspension: 625 mg once daily.

(Generic available)

• Oral suspension (lemon-lime flavor): 40 mg/mL; 125 mg/mL;
• Tablets: 20 mg; 40 mg; 160 mg;

• 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.

• Verify negative pregnancy test before starting therapy.

• Because of high dose, suspension is most convenient form for patients with AIDS.
• PO: May be administered with meals if GI irritation becomes a problem.
  • Shake suspension well before administering.

• Instruct patient to take megestrol as directed; do not skip or double up on missed doses. Missed doses may be taken as long as 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.
• May cause fetal harm. Advise females of reproductive potential to use effective contraception during and for at least 4 mo after therapy is completed. Advise patient to notify health care professional immediately if pregnancy is planned or suspected, and to avoid breastfeeding during therapy.

• 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.

Megace