Megefren (Megestrol Acetate)

Megestrol acetate is used in several oncologic and metabolic conditions where hormone modulation or appetite stimulation is required.

• Cachexia associated with cancer or AIDS: helps increase appetite and promote weight gain.
• Advanced breast cancer: provides antineoplastic activity by antagonizing estrogen‑driven tumor growth.
• Endometrial cancer: used as hormonal therapy to inhibit tumor progression.

• Megestrol acetate acts as an agonist at progesterone receptors, producing progestogenic effects that modulate endocrine pathways. Its glucocorticoid‑like activity contributes to appetite stimulation and may exert antineoplastic effects by influencing cell proliferation and apoptosis in hormone‑sensitive tumors.

Megestrol acetate may cause a range of adverse reactions that vary in frequency and severity.

Common Side Effects

• Nausea: mild to moderate gastrointestinal upset.
• Weight gain: increased appetite leading to excess caloric intake.
• Edema: peripheral fluid accumulation, often mild.
• Fatigue: generalized tiredness without exertion.
• Hot flashes: transient vasomotor symptoms.
• Increased appetite: heightened desire for food.

Serious or Rare Side Effects

• Thromboembolic events: deep‑vein thrombosis or pulmonary embolism.
• Adrenal suppression: reduced endogenous cortisol production.
• Severe allergic reaction: rash, swelling, or anaphylaxis.
• Hyperglycemia: elevated blood glucose levels, especially in diabetics.
• Cushingoid features: facial rounding, central obesity, and skin changes.

When prescribing Megestrol acetate, clinicians should consider several safety measures.

• Monitor blood glucose: hyperglycemia may develop, especially in diabetic patients.
• Assess thromboembolic risk: evaluate history of clotting disorders before initiation.
• Evaluate adrenal function: prolonged use can suppress endogenous cortisol.
• Use caution in cardiovascular disease: fluid retention may exacerbate heart failure.
• Avoid in known hypersensitivity: discontinue if allergic reactions occur.
• Store at ambient temperature: keep in the original container, protect from moisture and direct sunlight.

Megestrol acetate can interact with other medicines, affecting efficacy or safety.

Major Interactions (Avoid)

• Strong CYP3A4 inducers (e.g., rifampin, phenytoin): may reduce therapeutic levels.
• Strong CYP3A4 inhibitors (e.g., ketoconazole, clarithromycin): may increase exposure and risk of toxicity.
• Anticoagulants (e.g., warfarin): may enhance anticoagulant effect, increasing bleeding risk.

Moderate Interactions (Monitor Closely)

• Antidiabetic agents: may require dose adjustment due to altered glucose control.
• Antihypertensives: fluid retention can blunt blood‑pressure‑lowering effects.
• Non‑steroidal anti‑inflammatory drugs (NSAIDs): combined use may increase gastrointestinal irritation.