- What is megestrol, and how does it work (mechanism of action)?
- What are the uses for megestrol?
- What are the side effects of megestrol?
- What is the dosage for megestrol?
- Which drugs or supplements interact with megestrol?
- Is megestrol safe to take if I'm pregnant or breastfeeding?
- What else should I know about megestrol?
What is megestrol, and how does it work (mechanism of action)?
Megestrol is a synthetic female hormone belonging to the progesterone group. It is used for stimulating appetite and treating breast cancer. Progesterone is a hormone produced by the body, especially in women, that helps control the menstrual period as well as other body functions. How megestrol stimulates appetite or suppresses cancer is not understood. The FDA approved megestrol in September 1993.
What brand names are available for megestrol?
Megace, Megace ES, Megace Oral
Is megestrol available as a generic drug?
GENERIC AVAILABLE: Yes
Do I need a prescription for megestrol?
Yes
What are the uses for megestrol?
Megestrol is a drug prescribed for stimulating the appetite in patients with AIDS who have poor appetite or an unexplained significant weight loss. This medication is also used for treating breast cancer and weight loss associated with cancer.
What are the side effects of megestrol?
The most common side effects are:
- diarrhea,
- weight gain,
- nausea,
- rash,
- impotency,
- insomnia,
- mood swings,
- sweating,
- breakthrough menstrual bleeding,
- high blood pressure, and
- excess gas (flatulence).
Blood clots in legs and lungs may occur.
Megestrol may worsen existing diabetes or lead to new onset diabetes.
What is the dosage for megestrol?
The recommended dose for stimulating appetite is 800 mg per day of the regular megestrol suspension (40 mg/ml) or 625 mg per day of the ES formulation (125 mg/ml). Breast cancer is treated with 40 mg four times daily.

SLIDESHOW
Breast Cancer Awareness: Symptoms, Diagnosis, and Treatment See SlideshowWhich drugs or supplements interact with megestrol?
Indinavir (Crixivan) reduces blood concentrations of megestrol. An increase in the dose of megestrol should be considered.
Is megestrol safe to take if I'm pregnant or breastfeeding?
Megestrol may cause birth defects and should not be administered to pregnant women. Women should use contraception while taking megestrol.
Megestrol should not be used while breastfeeding due to potential adverse effects in the infant.
What else should I know about megestrol?
What preparations of megestrol are available?
Tablets: 20 and 40 mg. Oral suspension: 40 mg/mL or 125 mg/mL.
How should I keep megestrol stored?
Megestrol should be stored in a dry place at room temperature, 15 C-25 C (59 F-77 F).
Summary
Megestrol (Megace, Megace ES) is a drug prescribed for stimulating the appetite in patients with AIDS who have poor appetite or an unexplained significant weight loss. This medication is also used for treating breast cancer and weight loss associated with cancer. Review side effects, drug interactions, and pregnancy safety information prior to taking this medication.
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Breast Cancer
Breast cancer is an invasive tumor that develops in the mammary gland. Breast cancer is detected via mammograms, breast self-examination (BSE), biopsy, and specialized testing on breast cancer tissue. Treatment of breast cancer may involve surgery, radiation, hormone therapy, chemotherapy, and targeted therapy. Breast cancer risk may be lowered by managing controllable risk factors. What you should know about breast cancer Breast cancer is the most common cancer among American women. One in every eight women in the United States develops breast cancer. There are many types of breast cancer that differ in their capability of spreading (metastasize) to other body tissues. The causes of breast cancer are unknown, although medical professionals have identified a number of risk factors. There are 11 common types of breast cancer and 4 uncommon types of breast cancer. Breast cancer early signs and symptoms include a lump in the breast or armpit, bloody nipple discharge, inverted nipple, orange-peel texture or dimpling of the breast's skin (peau d'orange), breast pain or sore nipple, swollen lymph nodes in the neck or armpit, and a change in the size or shape of the breast or nipple. Breast cancer can also be symptom free, which makes following national screening recommendations an important practice. Breast cancer is diagnosed during a physical exam, by a self-exam of the breasts, mammography, ultrasound testing, and biopsy. Treatment of breast cancer depends on the type of cancer and its stage (0-IV) and may involve surgery, radiation, or chemotherapy.
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AIDS (Acquired Immunodeficiency Syndrome)
AIDS is the advanced stage of HIV infection. Symptoms and signs of AIDS include pneumonia due to Pneumocystis jiroveci, tuberculosis, toxoplasmosis, seizures, weakness, meningitis, yeast infection of the esophagus, and Kaposi's sarcoma. Anti-retroviral therapy (HAART) is used in the treatment of AIDS.
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A lump in the breast is almost always cancer. See AnswerHealth Solutions From Our Sponsors

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