Overview of the Medication Megace

Megace (megestrol acetate) is typically given to people who are very sick with breast cancerendometrial cancer, or AIDS. This drug is given to boost appetite and weight gain. In those patients who are very sick and prescribed Megace, this drug's hormone effects can be soothing and cause an increase in well-being, too.

Man scooping out salad onto a friend's plate

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Sometimes people who are older and underweight are prescribed Megace, but this drug's efficacy in an elderly population is unproven. Most of the research on Megace involves those with cancer or AIDS.

Megace is an endocrine-metabolic agent and synthetic hormone. Because Megace is a synthetic hormone, it has a variety of adverse effects which involve many organ systems spanning the entire body.

Mechanism of Action

Megace or megestrol acetate is a synthetic progestin that has antiestrogen properties and may affect the endometrium or lining of the uterus. Specifically, Megace interferes with the estrogen-receptor cycle and is thought to affect the pituitary gland in the brain. The pituitary gland secretes hormones that affect your muscles, kidneys, and various organs. Some experts believe that Megace boosts appetite through its effect on body metabolism (catabolic cytokines).

Clinical Indications

Megace is given to:

  • relieve suffering caused by endometrial cancer or breast cancer
  • increase appetite and stop weight loss in people with AIDS and cancer (cachexia)
  • boost appetite in prostate cancer
  • boost mood in people with AIDS and cancer
  • provide hormone therapy for endometrial and breast cancer

As mentioned earlier, there is no evidence-based support for the use of Megace as a treatment for appetite loss in older people.

Adverse Effects

Megace has no interactions with other drugs. However, Megace has wide-ranging clinical actions and can interfere with health and well-being in various ways, In the following list, possible adverse effects of Megace are followed by estimated prevalence.

  • hypertension (4% to 8%)
  • chest pain (1% to 3%)
  • palpitations (1% to 3%)
  • a headache (3% to 10%)
  • insomnia (1% to 6%)
  • depression (1% to 3%)
  • neuropathy or nerve weakness (1% to 3%)
  • skin rash (6% to 12%)
  • pruritis or skin itch (1% to 3%)
  • hyperglycemia or high sugars (6%)
  • breast enlargement or gynecomastia (1% to 3%)
  • diarrhea (10% and equal to placebo)
  • constipation (1% to 3%)
  • impotence (4% to 14%)
  • urinary incontinence (1% to 3%)
  • infection (1% to 3%)
  • eye problems (1% to 3%)
  • cough (1% to 3%)
  • fever (1% to 6%)
  • infection (1% to 3%)
  • enlarged liver or hepatomegaly (1% to 3%)

Of note, Megace should not be taken during pregnancy and can harm the fetus.

We included so many items on this list to prove a point: Megace is a hormone, and many people who take hormones will experience some negative side effects. Hormone therapy should be carefully considered and can sometimes exacerbate heart disease or cause severe depression. For this reason, Megace is s drug best reserved for people in end-stage care, not elderly people who need to gain weight.

If you're taking Megace and experience chest pain, nausea, vomiting, frequent urination, leg pain, or anything else that makes you feel terrible, make sure to discontinue use of the medication and see a physician immediately. If need be, call emergency services.

Megace is available in oral form as both a suspension and a pill. There are cheaper generic versions of this medication available.

Depending on the provider and patient worldview, one alternative to Megace in elderly patients is medical marijuana.

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