Megestrol Acetate 20mg Tablets

Megestrol acetate is a synthetic progestin. Its antineoplastic action in breast cancer is thought to be mediated via an anti-estrogenic effect, possibly by altering the estrogen receptor or by direct cytotoxic effects. In endometrial cancer, it may exert a direct cytotoxic effect. For appetite stimulation and weight gain in cachexia, the exact mechanism is not fully understood but is believed to involve modulation of cytokine production and direct effects on the hypothalamus.

Urgent Side Effects: Seek Medical Help Right Away

Although rare, some people may experience severe and potentially life-threatening side effects while taking this medication. If you notice any of the following symptoms, contact your doctor immediately or seek emergency medical attention:

Signs of an allergic reaction: rash, hives, itching, red, swollen, blistered, or peeling skin (with or without fever), wheezing, tightness in the chest or throat, difficulty breathing, swallowing, or talking, unusual hoarseness, or swelling of the mouth, face, lips, tongue, or throat.
Signs of high blood sugar: confusion, drowsiness, excessive thirst or hunger, frequent urination, flushing, rapid breathing, or fruity-smelling breath.
Signs of Cushing's syndrome: weight gain in the upper back or abdomen, moon face, severe headache, or slow wound healing.
Signs of adrenal insufficiency: severe nausea or vomiting, severe dizziness or fainting, muscle weakness, extreme fatigue, mood changes, decreased appetite, or weight loss.
Signs of high blood pressure: severe headache or dizziness, fainting, or changes in vision.
Shortness of breath, sudden weight gain, or swelling in the arms or legs.
Abnormal vaginal bleeding.
Mood changes.
Decreased libido.
Erectile dysfunction.
Fever.
Pain or numbness in the hands or wrists.
Tumor flare reaction: increased pain or tenderness at the tumor site, hot flashes, or other symptoms. Notify your doctor immediately if you experience any of these symptoms.
Blood clots: chest, arm, back, neck, or jaw pain or pressure; coughing up blood; numbness or weakness on one side of the body; difficulty speaking or thinking; changes in balance or vision; shortness of breath; or swelling, warmth, or pain in the leg or arm. Seek medical help right away if you experience any of these symptoms.

Other Possible Side Effects

Like all medications, this drug can cause side effects. While many people may not experience any side effects or only minor ones, it's essential to discuss any concerns with your doctor. If you experience any of the following side effects or any other symptoms that bother you or persist, contact your doctor:

Nausea or vomiting.
Headache.
Increased appetite.
Weight gain.
Insomnia.
Gas.
Fatigue or weakness.
Hair loss.
Hot flashes.
Excessive sweating.
* Diarrhea.

This list is not exhaustive. If you have questions or concerns about side effects, consult your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.

Before Taking This Medication: Important Information to Share with Your Doctor

It is essential to inform your doctor about the following:

If you have a known allergy to megestrol acetate or any component of this medication. Be sure to discuss the specifics of your allergy, including any symptoms you have experienced.
If you are taking dofetilide, as this may interact with the medication.
If you are pregnant or think you may be pregnant. Note that this medication should not be used to stimulate appetite during pregnancy.
If you are breastfeeding, as you should not breastfeed while taking this medication.

This list is not exhaustive, and it is crucial to discuss all your medications (including prescription, over-the-counter, natural products, and vitamins) and health issues with your doctor and pharmacist. They will help determine if it is safe to take this medication in conjunction with your other treatments and health conditions. Never start, stop, or adjust the dosage of any medication without first consulting your doctor.

It is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication. Regular blood tests will be necessary, as directed by your doctor, to monitor your condition. Be sure to discuss any concerns or questions with your doctor.

One of the potential side effects of this drug is the development of high blood sugar, which may lead to new-onset diabetes or worsen existing diabetes. It is crucial to check your blood sugar levels as instructed by your doctor.

This medication may also affect your body's natural production of steroids. If you experience a severe infection, undergo surgery, or suffer an injury, notify your doctor promptly. Additionally, if you experience severe dizziness, fainting, persistent nausea and vomiting, or excessive fatigue and weakness, seek medical attention immediately, as you may require steroid replacement therapy. Consult with your doctor to discuss the best course of action.

If you are pregnant or planning to become pregnant, it is vital to note that this drug may harm the unborn baby. To confirm that you are not pregnant, your doctor may require a pregnancy test before initiating treatment. To prevent pregnancy while taking this medication, use a reliable form of birth control. If you become pregnant or suspect you may be pregnant while taking this drug, contact your doctor immediately.

• Indinavir (decreased indinavir plasma concentrations)

• Warfarin (potential for increased INR, monitor closely)
• Glucocorticoids (additive effects, increased risk of adrenal suppression)

• Weight changes (gain or loss)
• Appetite changes
• Blood sugar fluctuations (e.g., increased thirst, urination)
• Signs of blood clots (e.g., leg pain/swelling, chest pain, shortness of breath, sudden vision changes)
• Signs of adrenal suppression (e.g., fatigue, weakness, dizziness, nausea, vomiting, low blood pressure)
• Fluid retention/edema
• Hot flashes
• Vaginal bleeding/spotting

Contraindicated in pregnancy (Category X). Megestrol acetate can cause fetal harm when administered to a pregnant woman. There is evidence of teratogenicity and adverse effects on the fetus.

Contraindicated during breastfeeding (L5). Megestrol acetate is excreted in human milk. Due to the potential for serious adverse reactions in the infant, including hormonal effects, a decision should be made whether to discontinue nursing or to discontinue the drug, taking into account the importance of the drug to the mother.

Safety and effectiveness have not been established in pediatric patients for cancer treatment. For cachexia, limited data exist, and use is generally not recommended due to potential for adverse effects on growth and development.

Use with caution in elderly patients. Elderly patients may be at increased risk for adverse effects such as thromboembolic events, hyperglycemia, and adrenal suppression. Dosage adjustments are generally not required based on age alone, but careful monitoring is warranted.

• Megestrol acetate is a progestin, not a corticosteroid, but high doses can cause adrenal suppression, requiring careful tapering if discontinued after prolonged use.
• While effective for appetite stimulation and weight gain in cachexia, it is associated with an increased risk of thromboembolic events (e.g., DVT, PE).
• Patients should be advised to take megestrol with food to enhance absorption.
• Monitor blood glucose levels, especially in diabetic patients, as hyperglycemia is a known side effect.
• The 20mg tablet strength is typically used for cancer indications, while higher doses (e.g., 400-800mg/day liquid or higher strength tablets) are used for appetite stimulation in cachexia.

• For advanced breast cancer: Tamoxifen, Aromatase inhibitors (e.g., Anastrozole, Letrozole, Exemestane), Fulvestrant, Chemotherapy.
• For advanced endometrial carcinoma: Other progestins (e.g., medroxyprogesterone acetate), Chemotherapy.
• For appetite stimulation/cachexia: Dronabinol, Corticosteroids (short-term), Mirtazapine, Ghrelin mimetics (e.g., Anamorelin - not available in all regions).

If your symptoms or health issues persist or worsen, it is essential to contact your doctor for further guidance. To ensure your safety, never share your medication with others or take someone else's medication. Some medications may come with an additional patient information leaflet, so it's a good idea to check with your pharmacist for more information. If you have any questions or concerns about your medication, don't hesitate to reach out to your doctor, nurse, pharmacist, or other healthcare provider. In the event of a suspected overdose, immediately call your local poison control center or seek emergency medical attention. When seeking help, be prepared to provide details about the medication taken, the amount, and the time it happened.