What are the recommended appetite enhancers for a patient with decreased appetite?

Recommended Appetite Enhancers for Decreased Appetite

For patients with concurrent depression and appetite loss, mirtazapine 7.5-30 mg at bedtime is the optimal first-line choice, addressing both conditions simultaneously with a favorable side effect profile including appetite stimulation and weight gain. 1

Patient Selection Algorithm

First: Assess for Depression

• If depression is present: Mirtazapine is the clear first choice, with dosing starting at 7.5 mg at bedtime for elderly patients or 15 mg for younger adults, with maximum dose of 30 mg at bedtime 1, 2
• Mirtazapine produces mean weight gain of 1.9 kg at 3 months and 2.1 kg at 6 months, with approximately 80% of patients experiencing weight gain 1, 2
• A full therapeutic trial requires 4-8 weeks to assess efficacy 1
• Avoid bupropion as it is the only antidepressant consistently shown to promote weight loss 2, 3

Second: For Patients WITHOUT Depression

Cancer Patients with Advanced Disease

Megestrol acetate (400-800 mg daily) is the most effective pharmacological option, improving appetite in approximately 25% of patients and producing modest weight gain in about 8% 4, 3

• Megestrol acetate is superior to placebo, dronabinol, and fluoxymestrone for appetite stimulation based on 30 RCTs 4, 3
• Critical safety concerns: Risk of thromboembolic events (including death in some studies), edema, impotence, vaginal spotting, and adrenal suppression 4, 1
• May attenuate benefits of resistance training, causing smaller gains or deterioration in muscle strength 1
• Duration should be restricted due to side effect profile 4

Short-Term Use in Advanced Disease (1-3 weeks)

Corticosteroids (dexamethasone 2-8 mg/day) offer faster onset of action but should be reserved for patients with shorter life expectancy 4, 2

• The antianorectic effect is transient and disappears after a few weeks 4
• Side effects emerge quickly: Myopathy, immunosuppression, insulin resistance (early), muscle wasting, and osteopenia (long-term) 4
• May be more suitable when other symptoms like pain or nausea need concurrent treatment 4

Cannabinoids (Dronabinol)

Dronabinol has limited evidence and is generally NOT recommended as first-line therapy 1, 3

• FDA-approved for AIDS-related anorexia at 2.5 mg twice daily (1 hour before lunch and dinner), with dose reduction to 2.5 mg once daily if side effects occur 5
• Showed statistically significant improvement in appetite at 4 and 6 weeks in AIDS patients, but only trends toward weight improvement 5
• Common side effects: Dizziness, confusion, somnolence, euphoria, paranoid reactions (18% required dose reduction) 5
• Serious risks: Seizures, cognitive impairment (especially in elderly), blood pressure changes, increased fall risk in elderly with dementia 5
• Multiple guidelines conclude insufficient evidence for routine use 1

Third: Special Population Considerations

Patients with Dementia

Appetite stimulants should NOT be used in patients with dementia who do not have concurrent depression 1, 3

• Evidence shows no consistent benefit and potentially harmful side effects outweigh uncertain benefits (89% consensus agreement) 1
• Three placebo-controlled trials found no significant effect of cannabinoids on body weight, BMI, or energy intake in dementia patients 1

Elderly Patients

• Start with lower doses and monitor closely for side effects 2
• Elderly patients, especially those with dementia, have increased risk of cognitive impairment, blood pressure changes, and falls with dronabinol 5
• Consider single daily dosing at bedtime to reduce nervous system side effects 5

Non-Pharmacological Interventions (Implement Concurrently)

These should be initiated alongside any pharmacological therapy:

Nutritional Strategies

• Oral nutritional supplements when dietary intake falls to 50-75% of usual intake, as these can increase energy and protein intake 1, 2, 3
• Serve energy-dense meals to meet nutritional requirements without increasing meal volume 2, 3
• Offer protein-enriched foods and drinks to improve protein intake 2, 3
• Make snacks available between meals 3

Social and Environmental Modifications

• Encourage shared meals with family or other patients to improve intake 1
• Provide emotional support during meals and ensure adequate feeding assistance 2, 3
• Offer smaller, more frequent meals with favorite foods 1

Medication Review

• Identify and discontinue medications that may contribute to poor appetite (e.g., iron supplements, multiple medications before meals) 1

Monitoring Requirements

• Regular reassessment is essential to evaluate benefit versus harm of pharmacological interventions 1, 2, 3
• After 9 months of mirtazapine treatment, consider dosage reduction to reassess need for continued medication 1
• Discontinue mirtazapine over 10-14 days to limit withdrawal symptoms 1
• Monitor for thromboembolic events with megestrol acetate 3
• Assess for hyperglycemia, muscle wasting, and immunosuppression with corticosteroids 3

Critical Pitfalls to Avoid

• Do not use appetite stimulants in end-of-life patients where focus should be on comfort and quality of life rather than nutritional goals 1
• Do not combine megestrol acetate with resistance training programs as it may attenuate muscle strength gains 1
• Do not use megestrol acetate in bed-bound patients due to increased risk of deep vein thrombosis 6
• Do not use dronabinol as first-line given limited efficacy data in most populations and significant side effect burden 1, 7