Dronabinol for Appetite Loss in Critical Illness

Evidence Assessment

The National Comprehensive Cancer Network acknowledges that cannabinoids have limited data to support their use for anorexia/cachexia in cancer patients, with megestrol acetate showing superior efficacy 1, 2
Guidelines do not support the systematic use of appetite stimulants, including dronabinol, for critically ill patients due to very limited evidence and potential adverse effects 3

Megestrol acetate (400-800 mg/day) is recommended as the primary pharmacological intervention for appetite stimulation in patients with serious illness when increased appetite is important for quality of life 4, 5
Approximately 1 in 4 patients treated with megestrol acetate will experience increased appetite and 1 in 12 will have measurable weight gain 4
Dexamethasone (2-8 mg/day) may be considered for short-term appetite stimulation in patients with limited life expectancy due to its rapid onset of action 5, 6
Mirtazapine can be useful for appetite stimulation, particularly in patients with concurrent sleep difficulties or mood disorders 7, 5
Olanzapine (5 mg/day) may be considered, especially for patients with concurrent nausea or anxiety 6

Address reversible causes of anorexia first (pain, constipation, nausea/vomiting, depression, oropharyngeal candidiasis) 2
Provide emotional support and specific behavioral strategies during meals, which can positively affect eating behavior and increase food intake 3
Consider nutrition consultation for calorie-dense, high-protein supplementation 1, 2

The European Society for Clinical Nutrition and Metabolism (ESPEN) guidelines explicitly state that limited and inconsistent evidence does not support a recommendation for dronabinol in cancer anorexia, despite potential to improve chemosensory perception 8
In a prospective randomized placebo-controlled multicenter trial of 164 patients with advanced cancer and anorexia-cachexia syndrome, cannabis extract or THC at 5 mg/day for 6 weeks did not improve appetite or quality of life 8
In a head-to-head RCT of 469 patients with cancer cachexia, megestrol acetate (800 mg/day) demonstrated significantly greater appetite and weight gain compared to dronabinol (2.5 mg twice daily), with the dronabinol-alone group showing the poorest outcomes 8
High drop-out rates due to adverse events were documented in clinical trials, with neuropsychiatric side effects being prominent 8

Do not use dronabinol as first-line therapy in cancer patients when superior alternatives (megestrol acetate) exist with better evidence 8