has been extensively studied as an appetite stimulant.
Clinical trials have demonstrated that megestrol is
- equally efficacious to dexamethasone
as an appetite stimulant;
- superior to dronabinol
in appetite stimulation and non-fluid weight gain;
- effective, when used concurrently with radiation therapy in lung or head and neck cancer, to reduce treatment associated weight loss; and
- associated with fewer side effects than corticosteroids.
However, despite these apparent benefits, available data suggests that weight gain is largely adipose tissue (not lean muscle) and only one study has demonstrated a quality-of-life benefit; no study has shown a survival advantage.
Overall only 20-30% of advanced cancer patients will have a significant response (weight gain > 5%), with a median response duration of 6-8 weeks.
The optimal timing to initiate treatment with megestrol (prophylactic or therapeutic) and the optimal duration of therapy are unknown.
Megestrol is dosed orally, once daily. There is an increasing dose/response curve from 160 to 800 mg/day; doses above 800 mg/day have no additional benefit. Different strategies include beginning at 400 mg per day and titrating for effect to 800 mg/day. Alternatively, dosing can begin at 800 mg/day.
Side effects can include thromboembolic events (use with caution in patients with a history of thromboembolism), adrenal suppression with insufficiency upon abrupt discontinuation, hypertension, hyperglycemia.
See reference for details.
Adapted from Salacz M. Palliative Care Network of Wisconsin. Fast facts and concepts #100. Megestrol acetate for cancer anorexia/cachexia. Internet. Accessed on January 25, 2016.