What is the proper dosing for Megace (megestrol acetate) for appetite stimulation?

From the Guidelines

Megestrol acetate (Megace) for appetite stimulation should be dosed at 160 mg daily, as this is the minimum efficacious dose and there is no evidence that higher doses have greater efficacy 1. The medication works by stimulating appetite through multiple mechanisms, including anti-inflammatory effects and modulation of neuropeptide signaling pathways involved in hunger regulation. Some key points to consider when using Megace for appetite stimulation include:

• The optimal dose is 160 mg daily, with no added benefit from higher doses 1
• Patients may begin to notice improved appetite within 1-3 weeks of starting treatment, though full effects may take up to 6 weeks
• Common side effects include fluid retention, thromboembolic events, adrenal suppression, and hyperglycemia, so blood glucose should be monitored in diabetic patients 1
• The medication should be used cautiously in patients with a history of deep vein thrombosis or pulmonary embolism
• Treatment duration varies based on clinical response but is typically continued as long as benefits outweigh risks and the patient maintains a positive response It's also important to note that a recent systematic review and meta-analysis of megestrol acetate revealed improved appetite and slight improvements in weight gain when using this drug to treat anorexia/cachexia in patients with cancer, but also highlighted the risk of thromboembolic phenomena and death 1. Overall, the use of Megace for appetite stimulation should be carefully considered and monitored, with attention to the potential benefits and risks, as well as the individual patient's response to treatment.

From the FDA Drug Label

DOSAGE AND ADMINISTRATION Breast cancer: 160 mg/day (40 mg q.i.d.). Endometrial carcinoma: 40 to 320 mg/day in divided doses. At least 2 months of continuous treatment is considered an adequate period for determining the efficacy of megestrol acetate. The proper dosing for megestrol acetate (Megace) for appetite stimulation is not directly stated in the provided drug label. However, the label does provide dosing information for breast cancer and endometrial carcinoma.

• The dose for breast cancer is 160 mg/day (40 mg four times a day).
• The dose for endometrial carcinoma ranges from 40 to 320 mg/day in divided doses. Since the label does not explicitly address appetite stimulation, no conclusion can be drawn regarding the proper dosing for this specific use 2.

From the Research

Proper Dosing for Megace for Appetite Stimulation

• The optimal dose of Megestrol acetate (MA) for appetite stimulation is not well established, as studies have shown varying results 3.
• A study published in 2002 suggested that 80 mg twice daily after meals is an appropriate starting dose of megestrol acetate for anorexia in advanced cancer, with possible dose escalation if needed 4.
• Another study recommended trying MA at a dose of 800 mg per day for no longer than 3 months in persons with a large excess cytokine production, and administering it with testosterone in men 5.
• A phase III evaluation of four doses of megestrol acetate (160,480,800, or 1,280 mg/d) found a positive dose-response effect for MA on appetite stimulation, but suggested using 160 mg/d as the initial treatment due to cost and inconvenience associated with higher doses 6.
• A phase II randomized clinical trial found that megestrol acetate at doses of 400 mg and 800 mg increases prealbumin in recently hospitalized older persons, but cortisol suppression is common at higher doses and may be persistent 7.

Key Findings

• Different doses of MA have been compared in studies, but no conclusive optimal dose has been established 3, 6, 7.
• Higher doses of MA may be more effective for appetite stimulation, but may also increase the risk of adverse events such as cortisol suppression and thromboembolism 5, 7.
• The choice of dose and treatment duration should be individualized based on patient response and tolerance 4, 6.