What appetite‑stimulating medication should be given to a patient with loss of appetite?

Management of Loss of Appetite

For patients with loss of appetite, the underlying cause determines treatment: mirtazapine 15-30 mg at bedtime is the first-line choice when appetite stimulation is needed alongside mood support, while megestrol acetate and dronabinol should generally be avoided due to limited efficacy and significant adverse effects. 1, 2, 3

Initial Assessment and Cause-Specific Approach

The treatment strategy depends critically on identifying the underlying condition:

• In cancer patients: Megestrol acetate and corticosteroids have demonstrated appetite-stimulating effects in randomized trials, though systematic use of appetite stimulants is not routinely recommended due to variable efficacy and side effect profiles 1

• In dementia patients: Systematic use of appetite stimulants like dronabinol or megestrol acetate is not recommended due to very limited evidence—only one small 12-patient study showed benefit with dronabinol, and results have been inconsistent 1

• In patients with depression or mood disorders: Mirtazapine 7.5-30 mg at bedtime provides dual benefits of appetite stimulation (through H1-receptor blockade) and antidepressant effects, making it the preferred agent 2, 3

Evidence-Based Medication Options

First-Line: Mirtazapine

• Dosing: Start 15 mg nightly, can increase to 45 mg as needed 3
• Mechanism: H1-receptor blockade increases appetite in approximately 80% of patients 2
• Advantages: Simultaneously addresses depression and appetite loss 3
• Monitoring: Watch for agranulocytosis (rare but serious) 3

Second-Line Options (Context-Dependent)

Dronabinol (Marinol):

• FDA-approved for AIDS-related anorexia at 2.5 mg twice daily (1 hour before lunch and dinner) 4
• Demonstrated statistically significant appetite improvement at weeks 4 and 6 in controlled trials 4
• Caution: Side effects (feeling high, dizziness, confusion, somnolence) occur in 18% of patients, often requiring dose reduction to 2.5 mg once daily 4
• Evidence in dementia is extremely limited (one 12-patient study only) 1

Megestrol Acetate:

• Shows appetite and weight benefits in some cancer populations 1
• Mixed results in geriatric populations with dementia (only 41% had dementia in available studies) 1
• Consider only in cancer-related cachexia when other options have failed 1

Medications to Avoid

Do NOT use these agents when appetite stimulation is the goal:

• SSRIs (escitalopram, fluoxetine, sertraline): Associated with appetite reduction and anorexia in 11% of patients 5, 2
• Bupropion/naltrexone, lorcaserin, phentermine: These are anorectic agents designed to suppress appetite for weight loss 1

Non-Pharmacological Interventions (Essential Adjuncts)

Even when medications are used, these strategies are critical 1:

• Caregiver education on nutrition-related problems and intervention strategies 1
• Feeding assistance: Verbal prompting, increased time during meals, supervision 1
• Environmental modifications: Ensure pleasant mealtime atmosphere, address behavioral issues 1
• Texture modification if dysphagia is present 1

Common Pitfalls to Avoid

1. Using appetite suppressants by mistake: Verify the patient is not on phentermine, lorcaserin, or bupropion/naltrexone—these will worsen the problem 1

2. Prescribing SSRIs without considering appetite effects: If antidepressant therapy is needed, choose mirtazapine over SSRIs when appetite is already compromised 2, 3

3. Expecting medication alone to solve the problem: Pharmacotherapy must be combined with nutritional support, caregiver education, and environmental modifications 1, 3

4. Using dronabinol or megestrol acetate indiscriminately: These have limited evidence outside specific populations (AIDS, cancer) and carry significant side effects 1, 4

Clinical Algorithm

1. Identify underlying cause (cancer, dementia, depression, acute illness)
2. If depression is present or suspected: Start mirtazapine 15 mg at bedtime 2, 3
3. If AIDS-related anorexia: Consider dronabinol 2.5 mg twice daily 4
4. If cancer-related cachexia: Consider megestrol acetate or corticosteroids after discussing risks/benefits 1
5. If dementia without depression: Focus on non-pharmacological interventions; avoid systematic appetite stimulant use 1
6. Always implement caregiver education and feeding assistance strategies regardless of medication choice 1