From the Guidelines
Megestrol acetate is a synthetic progestin medication primarily used to stimulate appetite and promote weight gain in patients with conditions causing unintentional weight loss, such as cancer or HIV/AIDS, with a typical dosage of 400-800 mg daily as an oral suspension. The use of megestrol acetate is supported by recent guidelines, including the 2020 ASCO guideline on the management of cancer cachexia, which found that megestrol acetate improved appetite, weight, and quality of life in patients with cancer cachexia 1. The optimal dose of megestrol acetate is between 480 and 800 mg per day, with higher doses associated with greater improvement in weight, but also increased risks of adverse events such as thromboembolic phenomena and death 1. Common side effects of megestrol acetate include fluid retention, hypertension, hyperglycemia, adrenal suppression, and increased risk of thromboembolic events, and it should be used cautiously in patients with diabetes, heart failure, or history of blood clots 1. The medication typically begins working within 1-3 weeks, and patients should be monitored for weight changes, fluid retention, and blood glucose levels, with treatment duration varying based on clinical response but generally continued as long as benefits outweigh risks. Some key points to consider when using megestrol acetate include:
- Monitoring for weight changes, fluid retention, and blood glucose levels
- Using the medication cautiously in patients with diabetes, heart failure, or history of blood clots
- Tapering the medication rather than abruptly discontinuing it after long-term use to prevent adrenal insufficiency
- Considering alternative treatments, such as combination therapy with other agents, for patients who do not respond to megestrol acetate or experience significant side effects 1. Overall, megestrol acetate is a useful medication for stimulating appetite and promoting weight gain in patients with cancer cachexia, but its use should be carefully monitored and individualized to minimize the risk of adverse events.
From the FDA Drug Label
Megestrol acetate oral suspension, USP is indicated for the treatment of anorexia, cachexia, or an unexplained, significant weight loss in patients with a diagnosis of acquired immunodeficiency syndrome (AIDS). The use of Megestrol acetate is for the treatment of:
- Anorexia
- Cachexia
- Unexplained, significant weight loss in patients with AIDS 2
From the Research
Use of Megestrol Acetate
The use of Megestrol acetate (MA) is primarily for the treatment of anorexia-cachexia syndrome in patients with cancer, AIDS, and other underlying pathologies. The key benefits of MA include:
- Improvement of appetite and weight gain in cancer and AIDS patients 3, 4, 5
- Potential to improve quality of life in patients with cancer and AIDS, although the evidence is not conclusive 3, 4
Mechanism of Action
The mechanism by which MA increases appetite is unknown, but it is thought to involve both behavioral and metabolic effects 5.
Dosage and Efficacy
The optimal dose of MA is not well defined, but higher doses are more likely to result in weight gain 3, 4. However, high-dose MA may also be associated with a higher risk of side effects, such as thromboembolic phenomena 3, 6.
Side Effects
Common side effects of MA include:
Patient Populations
MA has been studied in various patient populations, including:
- Cancer patients: MA has been shown to improve appetite and weight gain in cancer patients 3, 4, 5, 6
- AIDS patients: MA has been shown to improve appetite and weight gain in AIDS patients 3, 4, 7
- Patients with other underlying pathologies: The evidence for the use of MA in these patients is limited 3, 4