From the Guidelines
Megace (megestrol acetate) should be prescribed at a dose of 160-480 mg daily, as this range has been shown to be efficacious in stimulating appetite and promoting weight gain in patients with cancer, with no evidence of increased efficacy at higher doses 1. The optimal dose of Megace is likely around 160 mg daily, as this is the minimum efficacious dose that has been established in the literature 1.
- The medication can be taken orally as a single dose or divided into multiple doses.
- For appetite stimulation and weight gain in patients with cancer or AIDS-related cachexia, the dose can be titrated up to 480 mg daily if necessary and tolerated.
- Patients should take Megace with food to enhance absorption and minimize gastrointestinal side effects.
- It's essential to note that therapeutic effects on appetite and weight gain may take 2-4 weeks to become apparent, and the medication should be continued as long as benefits persist and side effects remain manageable.
- A more recent study has confirmed the efficacy of megestrol acetate in improving appetite and weight gain in patients with cancer-related anorexia/cachexia, with a systematic review and meta-analysis showing improved appetite and slight improvements in weight gain 1.
- However, it's crucial to weigh the benefits of Megace against the potential risks, including thromboembolic events and adrenal suppression, and to monitor patients regularly for these adverse effects 1.
From the FDA Drug Label
The recommended adult initial dosage of megestrol acetate oral suspension, USP is 800 mg/day (20 mL/day). In clinical trials evaluating different dose schedules, daily doses of 400 and 800 mg/day were found to be clinically effective.
The megestrol dose is 800 mg/day, and the frequency is daily. The dose can also be 400 mg/day, as both 400 and 800 mg/day were found to be clinically effective 2.
- The recommended initial dose is 800 mg/day.
- Alternative dose is 400 mg/day.
- Frequency for both doses is daily.
From the Research
Megace Dose and Frequency
- The optimal dose of Megestrol Acetate (MA) for cancer-related anorexia/cachexia is not well established, with studies suggesting varying doses and frequencies 3, 4.
- A systematic review and meta-analysis found that high-dose MA (>320 mg/day) tended to result in weight loss rather than weight gain, while low-dose MA (≤320 mg/day) had a more favorable effect on weight change 3.
- Another study compared different doses of MA and found no significant differences in weight gain, quality of life, or adverse events between lower and higher doses 4.
- A network meta-analysis found that high-dose megestrol acetate (≥400 mg/day) was significantly associated with weight gain and appetite improvement compared to placebo 5.
- A phase II randomized clinical trial in elderly patients with reduced appetite found that megestrol acetate suspension at doses of 400 mg and 800 mg daily increased prealbumin levels, but cortisol suppression was common at higher doses 6.
Dosage Considerations
- The dosage of MA may need to be individualized based on patient response and tolerance, with careful monitoring for adverse effects such as thromboembolism and cortisol suppression 3, 6.
- The frequency of MA administration is typically once daily, but the optimal dosing schedule has not been established 4, 5.
- Further studies are needed to determine the optimal dose and frequency of MA for cancer-related anorexia/cachexia and other conditions 3, 4, 5.