Side Effects of Megestrol and Other Important Information

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Also prescribed under a variety of brand names, such as Megace, this drug is a hormone known as progestins. Though more commonly prescribed for female-related ailments, this medication can help to treat certain conditions that men experience as well. This medication is prescribed for a variety of reasons, such as irregular menstrual cycle, infertility, in the prevention of endometrial hyperplasia, endometriosis and related pain, heavy menstrual bleeding, appetite and weight loss in AIDS patients, and to help treat uterine cancer, breast cancer, and kidney cancer. Patients should ensure they are aware of the side effects of megestrol and all of precautions associated with this drug. Progestins are essential in helping other hormones in the body work properly. Other possible uses of this medication can include iron deficiency anemia, prostate carcinoma, hot flashes, precocious, corpus luteum insufficiency, and polycystic ovarian syndrome.

How is this Medication Used?

This is an oral medication that comes in pill form. It must be taken exactly as prescribed and the dosage a patient is prescribed will be determined by how they are responding to this drug and their specific medical condition. It should always be taken at equal intervals and the same time every day.

Side Effects

The side effects of megestrol will vary from patient to patient. Most patients will experience the following common side effects:

  • Weight gain
  • Stomach upset
  • Gas
  • Sexual desire/ability reduction
  • Appetite changes (often increased appetite which results in the weight gain that is common with this drug)
  • Diarrhea
  • Trouble sleeping
  • Fever
  • Woman can have menstrual cycle changes including completely absent periods and unpredictable bleeding

The serious, yet rare, side effects require all patients to notify their doctor, and if they are bothersome enough, warrant the patient seeking medical care. These include:

  • Pounding and/or fast heartbeat
  • Swelling of hands/feet
  • Headache
  • Fatigue

Immediate medical attention is required if patients experience the following:

  • Chest pain
  • Mood and/or mental changes
  • Arm or leg redness, swelling, or pain
  • Trouble breathing
  • Confusion
  • One side of the body becoming weak and/or numb
  • Slurred speech
  • Vision changes that are sudden or severe


As with all medications, some diseases and conditions are contraindicated with this drug. The patient’s doctor will determine if this medication is safe for patient’s with the following medical conditions:

  • Adrenal gland disorders
  • Blood clots
  • Cushing’s syndrome
  • Diabetes
  • Kidney problems
  • Congestive heart failure
  • High blood pressure
  • Unusual vaginal bleeding

Drug Interactions

This drug and certain other drugs could interact with each other. Such drugs include:

  • Dofetilide
  • Diabetes medications
  • Indinavir

Warnings and Precautions

This medication could cause diabetes to worsen and high blood sugar levels. Patients on this medication, especially those with diabetes, who experience increased thirst, confusion, flushing, fruity breath odor, increased urination, drowsiness, rapid breathing, or any other signs of high blood sugar levels should notify their doctor immediately. If symptoms are particularly severe, they should seek immediate medical attention. Diabetes patients must be meticulous about monitoring their blood sugar levels.

Adrenal gland activity can decrease with this medication Patients expecting to have surgery or dental work must notify the health care provider performing it to help prevent complications. Once a patient stops using this drug, they may need to use a corticosteroid during times of stress, such as major surgery, trauma, or serious infection. Adrenal problems can cause unusual weakness, nausea, dizziness, and rapid weight loss.

As we age, our kidney begin to lose function. Since the kidneys are responsible for removing this drug from the body, the elderly can be more prone to side effects, as can those with kidney disorders.

Pregnant women absolutely cannot use this medication because it can harm an unborn child. Pregnancy must also be avoided when taking this drug. This drug may cause a nursing infant undesirable side effects because it may pass into breast milk, so breastfeeding should not be done when taking this drug.


RxList. Megace. Retrieved on September 8, 2010 from RxList: (2010). Progestin. Retrieved on September 8, 2010 from